Tuesday

February 9, 2016
Total # Posts: 1,926

**Mathematics**

3^(2x+1) = 12 We can rewrite this as: 3^(2x) * 3^(1) = 12 (3^2)^x = 12/3 9^x = 4 Get the natural logarithm of both sides: ln (9^x) = ln (4) x * ln(9) = ln(4) x = ln(4) / ln(9) We can further simplify this as: x = ln(2^2) / ln(3^2) x = 2*ln(2) / [2*ln(3)] x = ln(2) / ln(3) Hope...
*December 13, 2015*

**math**

Let l = length Let w = width It was said that the total length of fencing is 180 yards. Note that perimeter of rectangle is equal to: P = 2l + 2w Substituting, 180 = 2l + 2w 90 = l + w We can have an expression for length in terms of the width: l = 90 - w Recall that area of ...
*December 13, 2015*

**science**

Recall that speed is distance travelled over time, or v = d/t Rearranging the formula to solve for distance, d = v*t Substituting, d = (960 km/hr) * (1 hr & 50 min) Note that 1 hour = 60 minutes, so 50 minutes is 5/6 of an hour. Rewriting, d = (960) * (1 + 5/6) d = (960) * (11...
*December 13, 2015*

**St.martins**

Note that 1 km = 1000 meters, therefore 0.9 km = 900 meters To determine how many times he ran around the track, we just divide the total distance he travelled by the length of track: 900 / 150 = ? Hope this helps~ `u`
*December 13, 2015*

**AP Chemistry**

We'll reverse the 1st reaction: CH4 --> C + 2H2 ; ΔH = +74.6 We'll use the 2nd equation as is: C + 2Cl2 --> CCl4 ; ΔH = -95.7 We'll multiply the 3rd equation by 2: 2H2 + 2Cl2 --> 4HCl ; ΔH = -369.2 Now if we add the chemical equations, we&#...
*December 13, 2015*

**Math**

If blue to yellow is 4 to 1, then their total mixture is 5. Thus, the blue color makes up 4/5 of the mixture.
*December 2, 2015*

**Mathematics 3**

Let A = Aris' age Let R = Rico's age Let J = Jay's age From the problem, Aris is twice as old as Rico: A = 2R Jay is 24 years younger than Aris: J = A - 24 half of Aris' age six years ago was three less than one half the sum of Rico's age in four years and ...
*December 2, 2015*

**math**

Because the given side lengths of the triangle do not follow the triangle inequality theorem. The theorem states that the sum of any sidelengths of the triangle is greater than the length of the third side. In this case, 21 + 15 is not greater than 37.
*November 30, 2015*

**Science**

Recall that force is mass times the acceleration: F = m*a where m = mass (kg) a = acceleration (m/s^2) Substituting, F = 4 * 2.8 F = ? Solve for F. Units in Newtons. Hope this helps~ `u`
*November 29, 2015*

**Math**

Multiply the fraction by 100, so it becomes a percentage: 1/3 * 100 = 100/3 % Then simplify it and write it in mixed number form: 100/3 % = (99 + 1)/3 % = 33 1/3 % Hope this helps~ `u`
*November 6, 2015*

**Math**

Let x be the number. Write everything in math expression using x. Four time the square of a number: 4x^2 Is added to the product of -29 and the number: + (-29)x The result is 63: = 63 Combining them, we have 4x^2 + (-29)x = 63 or 4x^2 - 29x - 63 = 0 We have a quadratic ...
*November 6, 2015*

**MATH**

We have to find the least common multiple (LCM) of 3, 4 and 5. LCM is the smallest number that when divided by 3 or 4 or 5 should give no remainder. Their LCM is 60. Since the problem is asking "with a remainder of 2", we just add 2 to 60, therefore it's 62.
*November 6, 2015*

**Physics**

In Rutherford's model of atom, it was observed that the atom is mostly empty space, the mass of the atom is concentrated at the center (nucleus), and electrons revolve around the nucleus like a mini solar system. I think it's C.
*November 6, 2015*

**Physics**

(a) Maximum height formula for projectile motion: H,max = (vo,y)^2 / 2g or H,max = (vo)^2 * sin^2 (θ) / 2g where vo = initial velocity θ = angle of release (wrt to horizontal) g = acceleration due to gravity = 9.8 m/s^2 Substituting, H,max = (400^2) * (sin (35))^2...
*November 6, 2015*

**Physics**

This problem involved half projectile. initial velocity, vo = 20 m/s time of flight, t = 7 s (a) Simply use the formula to get the height, h: h = vo*t - (1/2)gt^2 (b) To get the final vertical velocity or terminal velocity (vf), use the formula: (vf)^2 - (vo)^2 = 2gh (c) Use ...
*November 6, 2015*

**math**

Let t be the time. Since Julie's and the escalator's rates are on opposite directions, we can represent it as one of them (+) and the other (-). Rate is distance traveled over time, or r = d/t or solving for d, d = r*t Then we write the equation: (Julie's distance...
*November 6, 2015*

**Chemistry**

I think it's (B) Metals. Though I agree with you, it's got to be more than 2/3 of all elements.
*November 6, 2015*

**gaya ,college science**

Alkaline Earth metals belong to group II in the periodic table. Actually there's nothing in the choices that belongs to group II. Carbon belongs to group IV, Sodium belongs to group I, while Zinc and Iron are found in transition metal group.
*October 18, 2015*

**Math**

Rewrite all fractions such that their denominators are the same, by getting their least common denominator (LCD). Their LCD is 18, therefore, 2/3 = 12/18 5/6 = 15/18 4/9 = 8/18 2/9 = 4/18 Now arrange it in ascending order. Hope this helps~ :3
*October 18, 2015*

**Algebra help plz**

Recall that for a given quadratic equation, x^2 - (sum of roots)x + (product of roots) we can rewrite the first quadratic eqn as x^2 + 2x - 3/2 = 0 Therefore, sum of roots is -2 and their product is -3/2, or € + ß = -2 €ß = -3/2 Since were looking for p (...
*October 18, 2015*

**Math**

The sum of the ages of Devonte and Anna is 107 years. 11 years ago, Devonte's age was 4 times Anna's age. How old is Devonte now?
*September 20, 2015*

**College Algebra **

Randall is 105 years old. Colleen is 5 years old. How many years until Randall's age is 5 times Colleen's age?
*September 20, 2015*

**Math**

Bradley is 4 years older than Amanda. In 3 years the sum of their ages will be 64. How old is Bradley now?
*September 20, 2015*

**Math**

The sum of the ages of Jared and Caitlyn is 80 years. 8 years ago, Jared's age was 3 times Caitlyn's age. How old is Jared now?
*September 20, 2015*

**algebra**

Let a = angle Let b = the other angle 45 less than the sum of these angles is (a + b) - 45
*September 19, 2015*

**P6 maths**

Let n = number of boys or girls Let p = received pizza by girls Let 2p = received pizza by boys Each girl ate 4/9 of a pizza and they finished all pizzas that were given to them: 4/9 * n = p Each boy ate 3/4 of a pizza and they had 3 3/4 pizzas left: 3/4 * n = 2p - 3 3/4 ...
*September 19, 2015*

**algebra**

Recall that rate is distance traveled over time, or r = d/t Solving for distance, we have d = rt Let r = speed of car Let t = time it takes to travel 144 miles Thus, rt = 144 ; equation (1) If it had traveled 4 mph faster, time it takes to travel the same distance would be ...
*September 18, 2015*

**math**

Yes, it's -12
*September 18, 2015*

**Math**

Recall that area of square is length of a side multiplied by itself, or A = s^2 We can first convert 2 m to cm. One meter is equivalent to 100 cm, therefore, 2 m = 200 cm Substituting, A = s^2 A = 200^2 A = 40000 cm^2 Hope this helps~ :3
*September 18, 2015*

**maths**

28 + 30 = 58 m
*September 12, 2015*

**maths**

1 hour is 60 minutes so, 5 hours & 30 minutes = 300 minutes + 30 minutes = 330 minutes Half of this is 165 minutes. 165 / 60 = 2 remainder 45 Therefore he spent 2 hours & 45 minutes for the ride.
*September 12, 2015*

**maths**

start: 0 cm 1st minute: 0 + 3 - 2 = 1 cm 2nd minute: 1 + 3 = 4 cm Therefore after 2 minutes the ant already climbed to the top (and didn't slip).
*September 12, 2015*

**Science**

Speed is distance traveled over time, or v = d/t Let x = time needed for the next 60 km 120 km/hr (average) = [(speed1) + (speed2)] / 2 120 = (60 + (60/t)) / 2 240 = 60 + 60/t 60/t = 240 - 60 60/t = 180 km/hr (speed2) time needed to achieve this speed is t = 60/180 = 1/3 hr
*September 12, 2015*

**Algebra 2**

I interpreted it as: 2/x + 1/(2x) = 4/(2x) + 1/(2x) = 5/(2x) But we can also interpret it as: 2/x + (1/2)x = 2/x + x/2 = 4/(2x) + x^2/(2x) = (4 + x^2) / 2x It depends on the expression is shown or typed. Placing parenthesis can help clarify the expression. hope this helps~ `u`
*September 12, 2015*

**ap calculus**

I interpreted it as: [ (-1/2 - h) - 1 ] / h Therefore, = ( -h - 3/2 ) / h = (-2h - 3) / 2h = -(2h + 3) / 2h
*September 11, 2015*

**math**

Yes, the 9 in 259 is in the ones place, while the 9 in the .689 is in the thousandths place.
*September 11, 2015*

**CALCULUS**

Even: Replace t to -t, and if the resulting function is still the same, that is, f(-t) = f(t), then it is even. And the graph is symmetric about the y-axis. Odd: Replace t to -t, and if the resulting function is the negative of the original function, that is, f(-t) = -f(t), ...
*September 11, 2015*

**algebra**

It decreases from x = negative infinity to 2, then becomes constant at x = 2 onwards.
*September 11, 2015*

**Maths-Proportions**

#1 Recall that rate is distance traveled over time. r = d/t or solving for distance, d = rt We can therefore write the proportion as (rate1)*(time1) = (rate2)*(time2) (500)*(8.4) = (420)*(time2) Now solve for time2. Units in hours. #2 Same what you'll do here in #2. (rate1...
*August 22, 2015*

**Math- Need Help**

No, both the x and y values are incorrect. Notice in your elimination method, you forgot to multiply one of the equations by -1 so that when added will cancel the variable y. This one: 15x + 12y = 18 16x + 12y = 20 should be: 15x + 12y = 18 -16x - 12y = -20 so that when added...
*August 21, 2015*

**Chemistry**

The given percentage for C and H do not add up to 100%. There might be a typo or incomplete info given...
*August 21, 2015*

**math.fraction**

1/2 = red 1/4 = blue ? = green Since one whole is 1, then the sum of the fractions must be equal to 1. 1/2 + 1/4 + (green) = 1 green = 1 - (1/2 + 1/4) green = 1 - (3/4) green = 1/4
*August 21, 2015*

**psychics**

(B) How high does the ball go? Since the ball is in uniformly accelerated motion, we can use the formula, vf^2 - vo^2 = 2gh where vf = final velocity vo = initial velocity g = acceleration due to gravity h = height Since at maximum height, the ball stops moving (vf = 0). Thus...
*August 20, 2015*

**Chemistry Ap**

A sprinter completes the 100 yard dash in 9.30 seconds. How long would it take her to complete 100. meters if she continued at the same speed? 1. 10.2 sec 2. 10.9 sec 3. 10.7 sec 4. 9.30 sec
*August 13, 2015*

**Math**

d / 4
*August 7, 2015*

**math**

We're going to perform operations on a + 1/a = 6 until we arrive at a^2 + 1/a^2. Square both sides. (a + 1/a)^2 = 6^2 a^2 + a*1/1 + a*1/a + 1/a^2 = 36 a^2 + 2 + 1/a^2 = 36 a^2 + 1/a^2 = 36 - 2 a^2 + 1/a^2 = 34 Hope this helps~ `u`
*August 6, 2015*

**Geometry**

V,cube = sidelength^3 V,cube = (1 cm)^3 V,cube = 1 cm^3 Since there are 20 ice cubes, V = 20 cm^3 V,cylinder = pi * r^2 * h V,cylinder = 3.14 * 3.5^2 * 9 V,cylinder = 346.185 cm^3 This is the volume of mug when full. Since 20 cm^3 is allotted for the ice cube, thus, 346.185 - ...
*August 6, 2015*

**physics**

Acceleration is change in velocity over time, or a = (v2 - v1) / t Substituting, a = (0 - 9) / 1.5 a = ? Now solve for a, note that it's negative since the final velocity is smaller than the initial velocity. Units in m/s^2 Hope this helps~ `u`
*July 22, 2015*

**chemistry**

From the periodic table, the molar weight of Na and Cl: Na - 23 Cl - 35.45 Thus molar mass of NaCl is 58.45 g/mol Molarity is moles solute over liters of solution. To get the moles, we divide the given mass by the molar mass: 5.85 g NaCl / 58.45 g/mol = 0.10 mol NaCl Thus, M...
*July 22, 2015*

**math**

Recall geometric mean. Let g be the geometric mean, so the geometric mean of a1, a2, a3 ... an is equal to g = nth root of (a1 * a2 * ... * an) Applying this to the problem, we have only two terms involved, which is 2x and 19x-2, thus n = 2. And g is given, which is 7x-2. ...
*July 18, 2015*

**Physics**

You should draw a free-body diagram. Represent the unknown forces with variables. Let F1 = force on the left side Let F2 = force on the right side Since the ropes are tied 60 degrees from the vertical, it's 90 - 60 = 30 degrees from the horizontal. Summation of all forces ...
*July 18, 2015*

**Math**

Operations should be performed in order PEMDAS: Parenthesis - Exponent - Multiplication - Division - Addition - Subtraction. But Multiplication and Division operations can be performed from left to right, no need to perform multiplication first then division. That is also ...
*July 18, 2015*

**physics**

We can use the formula: vf^2 - vo^2 = 2ad where vf = final velocity vo = initial velocity a = acceleration d = distance Substituting, 300^2 - 0^2 = 2(a)(0.9) a = ? Now solve for a. Units in m/s^2 Hope this helps~ `u`
*July 18, 2015*

**physics**

a. The stone is experiencing free fall, and therefore the motion involved is uniformly accelerated motion (UAM). We can use the formula, h = vo*t - (1/2)gt^2 where vo = initial velocity t = time g = acceleration due to gravity = 32.2 ft/s^2 Since it's free fall, vo = 0. ...
*July 15, 2015*

**physics**

a. The stone is experiencing free fall, and therefore the motion involved is uniformly accelerated motion (UAM). We can use the formula, h = vo*t - (1/2)gt^2 where vo = initial velocity t = time g = acceleration due to gravity = 32.2 ft/s^2 Since it's free fall, vo = 0. ...
*July 15, 2015*

**math**

Let n = number of eggs she bought. It was said she used 1/2 of them, then 1/4 of remainder, then she had 9 eggs left. Thus, (total eggs) minus (used eggs) equals the 9 eggs remaining, or n - [(1/2)n + (1/4)(1/2)n] = 9 Solving for n, n - (0.5n + 0.125n) = 9 0.375n = 9 n = 9 / 0...
*July 14, 2015*

**Science**

It's the third one, the 10.0m/s[E] since it has direction, which makes it a 'vector' quantity. The other three choices only measure the speed, while 10.0m/s[E] is velocity.
*July 3, 2015*

**Chemistry**

Their outer shell is already full, so they won't react easily. For Helium, that's 2 electrons, while for the rest of noble gases, it's 8 electrons.
*July 3, 2015*

**MATH**

The answer is yes for both questions.
*July 3, 2015*

**algebra**

Well this is just direct substitution of the given values. I'll do #1 and #2, and you do the rest: #1. apx + 1 = ? Since it was given that a = -10, p = -1 and x = 6, substituting, (-10)(-1)(6) + 1 = ? 60 + 1 = 61 #2. ry - c = ? Since it was given that c = -2, r = 3, and y...
*July 3, 2015*

**Chemistry**

Moles is given mass divided by the molar weight, or n = m / MW Substituting, n = 0.50 / 4 n = 0.125 mol He
*July 3, 2015*

**calculus**

A = Ao*e(^0.000124t) If the final amount, A, is equal to 10% of initial amount, Ao, thus 0.1*Ao = Ao*e(^0.000124t) 0.1 = e(^0.000124t) Get the ln of both sides: ln (0.1) = ln(e(^0.000124t)) ln (0.1) = 0.000124t Now solve for t. Just one clarification, I think the exponent of e...
*July 3, 2015*

**college geometry**

Let x = angle It was said the other angle is 30 deg more than four more the smaller, so Let 4x + 30 = other angle Since complementary angles sum up to 90 deg, x + 4x + 30 = 90 5x + 30 = 90 x = ? Now solve for x. Hope this helps~ `u`
*July 3, 2015*

**chemistry**

Assuming the gas is ideal, we can use Boyle's Law: P1 * V1 = P2 * V2 where P is pressure and V is volume. Substituting, 1.4 * 20.9 = P2 * 12.9 P2 = ? Units in atm. Hope this helps~ :3
*June 18, 2015*

**chemistry**

First write the balanced reaction: 2 NaOH + MgCl2 ---> Mg(OH)2 + 2 NaCl Then we determine the moles of each reactant using the given volume and concentration (molarity). Recall that molarity is moles of solute per liter solution, or M = n / V Solving for moles, n = M * V ...
*June 14, 2015*

**math**

Calculate the determinant (3 x 3 matrix). Then divide it by two and get the absolute value. That's the area. Let the z-coordinate be equal to 1: -10 | 5 | 1 15 | 5 | 1 10 | 12 | 1 The determinant of this set up is 175. Area is therefore, | 175/2 | = 87.5 units Hope this ...
*June 13, 2015*

**Maths**

If that means log 'base 10' then, log (y) + 2*log (x) = 2 Recall that we can rewrite the number that is multiplied by the the log expression as exponent of the term inside the log. For instance, a * log (x) = log (x^a) Thus, log (y) + log (x^2) = 2 Recall that when log...
*June 13, 2015*

**Math**

1/13 = 0.076923 076923 ... You can see here that the repeating numbers are 076923. There are six numbers in all so, 100/6 = 16 remainder 4 Counting four places, the 100th place is 9.
*May 30, 2015*

**Math**

Yes it is. :)
*May 30, 2015*

**MATH**

The given expression could mean a lot of things. It's because of the arrangement and lack of brackets/parenthesis. I suggest you type it again. It could mean for example, 0.4771 = x / (2.303*8.14[(50/323)*373]) Thus in this case, x = 516.42 It could also mean, 0.4771 = (x...
*May 28, 2015*

**Math**

Breadth is also the width. recall that area of rectangle is length multiplied by width: A = l * w Substituting, 900 = l * 45 l = 900 / 45 l = 20 m
*May 28, 2015*

**maths**

The given expression could mean a lot of things. It's because of the arrangement and lack of brackets/parenthesis. I suggest you type it again. It could mean for example, 0.4771 = x / (2.303*8.14[(50/323)*373]) Thus in this case, x = 516.42 It could also mean, 0.4771 = (x...
*May 28, 2015*

**Algebra**

No, it's not C. f(-3) means substitute x = -3 to the function: f(x) = x^2 - 4x + 3 f(-3) = (-3)^2 - 4(-3) + 3 f(-3) = 9 + 12 + 3 f(-3) = ?
*May 28, 2015*

**chemistry**

From the periodic table, the atomic masses of each are: K = 39 Mn = 55 O = 16 Divide the percentage to the respective atomic mass: K: 24.8 / 39 = 0.636 Mn: 34.77 / 55 = 0.632 O: 40.5 / 16 = 2.531 Divide each by the smallest number. The smallest number here is 0.632: K: 0.636...
*May 28, 2015*

**Chemistry**

First we determine the limiting reactant. The molar mass of NH3 is 17 g/mol. Getting the moles of NH3, we just divide the given mass by the molar mass: 25 g / 17 g/mol = 1.47 mol NH3 We determine the moles of NO produced by making mole ratios from the balanced reaction, such ...
*May 28, 2015*

**college geometry**

Use the distance formula: d^2 = (y2 - y1)^2 + (x2 - x1)^2 where d = distance (x1, y1) and (x2, y2) = points Thus, 3.5^2 = (3 - 3)^2 + (7 - b)^2 12.25 = 0 + 49 - 14b + b^2 Now solve for b.
*May 27, 2015*

**Math**

Your answer is actually correct. It should be raised to -6, not -5. For the solution: 1 Light Year = 9.46 x 10^12 km Thus, 58,000,000 km * (1 light year / 9.46 x 10^12 km) = 6.131 x 10^-6 light year
*May 18, 2015*

**Math**

You need to type it again and use parenthesis or brackets. It's necessary, because it's difficult to interpret the expression above.
*May 18, 2015*

**Calculus**

lim f(x) as x-->5 = 7
*May 18, 2015*

**math**

Let x = width Let 2x = length Perimeter of rectangle: P = 2*(length + width) Substitute: 60 = 2*(2x + x) 60 = 2*3x 60 = 6x x = 10 ft (width) 2x = 20 ft (length)
*May 17, 2015*

**Algebra**

This is a Fibonacci sequence, where the next term is the sum of two preceding terms. For instance the 3rd term (which is 1), is the sum of -2 and 3, and the 4th term (which is 4), is the sum of 3 and 1, and so on. Therefore, -2, 3, 1, 4, 5, 9, 14, 23, 37, 60, ...
*May 17, 2015*

**Math**

123 / 350
*May 17, 2015*

**Math**

Light Year is the distance traveled by light in one year. The speed of light in vacuum is approximately 3 x 10^5 km/s. And 1 year = 31,536,000 seconds. Thus, 1 Light-Year = 3 x 10^5 km/s * 31,536,000 s = 9.4608 x 10^12 km
*May 17, 2015*

**Math**

The geometric sequence is 1/4 , 1/16 , 1/64 , 1/256 , ... And the ratio is r = 1/16 / (1/4) = 1/4 This infinite geometric sequence converges because the ratio is in the range of -1 < r < 1. Getting the sum, we use the formula, S = a1 / 1 - r S = 1/4 / (1 - (1/4)) S = 1/4...
*May 17, 2015*

**maths**

String P is 3 times as long as string Q: P = 3Q String R is 3m longer than half the total length of strings P and Q: R = (1/2)(P + 3Q) + 3 The total length of all three strings is 5400 cm: P + Q + R = 5400 Substituting (such that everything is in terms of Q): 3Q + Q + (1/2)(3Q...
*May 17, 2015*

**Geometry**

Let n = pints of blue paint needed Use ratio and proportion. 3 blue : 4 red = n : 14 red Rewriting, 3/4 = n/14 n = (3/4) * 14 n = 42/4 n = 21/2 pints of blue paint
*May 17, 2015*

**science**

Percent Yield = (Actual Yield / Theoretical Yield) x 100 I think your data is insufficient, since we don't know how much is the theoretical yield.
*May 17, 2015*

**maths**

Let x = theta 2 cos(2x - π) = -2 Divide everything by 2 cos(2x - π) = -1 Expand the left side by applying the difference of cosines: cos(A ± B) = cos(A)cos(B) ∓ sin(A)sin(B) Thus, cos(2x)cos(π) + sin(2x)sin(π) = -1 cos(2x)*(-1) + sin(2x)*(0...
*May 17, 2015*

**math**

When an object is immersed completely in water, the displaced volume of water is equal to the volume of the object. The volume of cube is given by V = s^3 where s = side length Thus, V = 5.5^3 V = 166.375 cm^3 The volume of cylinder is given by V = π(r^2)(h) where π...
*May 17, 2015*

**math**

Well you already have the steps. :) (1) First, use the slope formula to find slope: m = (y2-y1) / (x2-x1) From the table of values, let's take the first two points (2,1) and (4,2), and substitute them into the formula for slope: m = (y2-y1) / (x2-x1) m = (2 - 1) / (4 - 2) ...
*May 15, 2015*

**trigonometry**

Recall that sin(A ± B) = sin(A)cos(B) ± cos(A)sin(B) Thus, sin(6x)cos(11x) - cos(6x)sin(11x) = -0.1 sin(6x - 11x) = -0.1 sin(-5x) = -0.1 -sin(5x) = -0.1 sin(5x) = 0.1 5x = sin^-1 (0.1) x = [ sin^-1 (0.1) ] / 5
*May 15, 2015*

**Math**

(sin^2 (x) - 1)^2 = cos(2x) + sin^4 (x) We'll only modify the left side. Expand the left side: (sin^2 (x) - 1)^2 sin^4 (x) - 2 sin^2 (x) + 1 Recall that 1 = cos^2 (x) + sin^2 (x) : Pythagorean identity. sin^4 (x) - 2 sin^2 (x) + cos^2 (x) + sin^2 (x) sin^4 (x) + cos^2 (x...
*May 15, 2015*

**Caclulus**

Yes it is. :)
*May 15, 2015*

**Math.**

4^4 / 4^6 One way to solve this is to expand the numerator and denominator and simplify the fraction to its lowest term. Another way to solve this is to apply some laws of exponent. We can see here that the numerator and denominator has a term with the same base (which is 4). ...
*May 15, 2015*

**math**

Tens = 7 Ones = five less than the tens = 2 Hundreds = four times the ones = 8 Thousands = same as hundreds = 8 Let n = ten thousands digit If their sum is 33, n + 7 + 2 + 8 + 8 = 33 n = 8 Thus the number is 88,872 Hope this helps~ `u`
*May 15, 2015*

**Calc 1**

Derivative of displacement (with respect to time) is velocity. Derivative of velocity (with respect to time) is acceleration. Thus, v(t) = ∫ (a(t)) dt v(t) = ∫ (t + 6) dt v(t) = (1/2)t^2 + 6t + C To find C, you know that at t = 0, v(0) = 4. You can substitute it ...
*May 15, 2015*

**Calc 1-oops**

I mean for the second question, integrate v(t) further and evaluate from t=0 to t=4: D(t) = ∫ v(t) D(t) = ∫ (t^2 + 2t - 3) D(t) = (1/3)t^3 + t^2 - 3t + C at t = 0: D(0) = (1/3)(0)^3 + (0)^2 - 3(0) + C D(0) = C at t = 4: D(4) = (1/3)(4)^3 + (4)^2 - 3(4) + C D(4) = ...
*May 15, 2015*

**Calc 1**

Derivative of displacement (with respect to time) is velocity. Derivative of velocity (with respect to time) is acceleration. Thus, v(t) = ∫ (a(t)) dt v(t) = ∫ (2t + 2) dt v(t) = t^2 + 2t + C It was said that at t = 0, v(0) = -3. v(0) = (0)^2 + 2(0) + C = -3 v(0...
*May 15, 2015*

**Math**

If you draw the figure, you'll have a right triangle with the ladder as the hypotenuse. Let x = how far up the wall the ladder goes We can use sines: sin (angle) = opposite / hypotenuse sin (15°) = x / 12 x = 12 sin (15°) x = ? Units in meters. Hope this helps~ `u`
*May 15, 2015*

**Calc 1**

Check you other posts, the questions are related. Derivative of displacement (wrt time) is velocity. Thus, integral of velocity is displacement. D(t) = ∫(t^2 − 2t − 15) dt D(t) = ? After you solved for the integration, evaluate this from time t=1 to t=7.
*May 15, 2015*