Sunday

November 29, 2015
Total # Posts: 1,917

**Algebra**

Yes, they are all equivalent. To prove, assume a real value of x, for instance, x = 2. Then we substitute this value to each expression. The answers must be equal since the expressions are equivalent: 1800(x+20) ; x=2 1800(2+20) = 1800(22) = 39,600 1800x + 20(1800) ; x=2 1800(...
*October 24, 2013*

**math**

(a) To get the maximum profit, we differentiate the given function with respect to u. And then equate everything to zero (because at maximum, the slope is zero): P = -0.032u^2 + 46u - 3000 dP/du = -0.064u + 46 0 = -0.064u + 46 0.064u = 46 u = 718.75 (this is the number of ...
*October 24, 2013*

**math-correction**

*lol, sorry it shouldn't be dA/dt, rather dA/dW = 62.5 - 2W but it won't affect the answer anyway. (it's just that you might wonder where the variable t came from) ^^;
*October 22, 2013*

**math**

Since there is additional 15 m which is part of one side of the wall, we can say that the total fencing material is 110 + 15 = 125 m Recall that perimeter of rectangle is just P = 2(L + W) where L is the length and W is width. Substituting, 125 = 2(L + W) 62.5 = L + W, or L = ...
*October 22, 2013*

**math**

Let A = number of Aaron's cards Let B = number of Benga's cards From the first statement, the total number of their cards is 976, so A + B = 976 From the second statement, B = 7A Thus we can say, A + 7A = 976 8A = 976 A = 122 B = 854 Now, let x = number of cards that ...
*October 22, 2013*

**chemistry**

First separate the reaction into reduction and oxidation reactions. Then add the right number of electrons to balance the charges. Reduction: Mn(2+) -> Mn(5+) Mn(2+) -> Mn(5+) + 3e- Oxidation: Sn(2+) -> Sn Sn(2+) + 2e- -> Sn And then balance both reactions such ...
*October 21, 2013*

**Algebra**

Let n be the number (n / -9) + 10 = 11 Solving, -n / 9 = 11 - 10 -n / 9 = 1 n = -9 Hope this helps :3
*October 21, 2013*

**Math**

Is that division, like this, (2^4 * 3^9) / (3^5 * 2^7) ? If it is, then, yep, the answer is 2^-3 * 3^4.
*October 21, 2013*

**Chemistry-correction**

*sorry, my conversion of 2.5 kg to g is wrong. The equation should be Q = (2500 / 200.6)*(28.0)*(-6 -(-20))
*October 21, 2013*

**Chemistry**

Through out the temperature range, Hg remains as liquid. Recall that heat released or absorbed is given by Q = m*c*(T2 - T1) where m = mass c = specific heat T = temperature Note that molar mass of Hg is 200.6 g/mol. Substituting, Q = (250000 / 200.6)*(28.0)*(-6 -(-20)) Q = ? ...
*October 21, 2013*

**math**

Slope intercept form is y = mx + b. We just convert the given equation in this form: 2x + y = -7 y = -2x - 7
*October 21, 2013*

**college algebra**

sqrt(x) + 7 Domain is the set of all possible values of x. Here, note that x is inside a squareroot radical sign and therefore cannot be less than zero. Thus domain is all real numbers greater than or equal to zero. In symbols: [0 , +infinity) Hope this helps :)
*October 21, 2013*

**math**

x^2 + x - 20 = (x + 5)(x - 4)
*October 21, 2013*

**math**

x^2 + 9x +18 = (x + 3)(x + 6)
*October 21, 2013*

**college physics**

a. Of course, one way for athlete 1 to overtake athlete 2 is for him to accelerate (that is, if v2 > v1). But since the given are constant speeds, surely v2 MUST BE LESS THAN v1 in order for athlete 1 to overtake athlete 2, WITHOUT accelerating. b. Recall that the distance ...
*October 21, 2013*

**Science help! URGENT. Check answers**

1. Nope. If the net forces are zero, it means that the object is at an equilibrium state (may be static of dynamic), and thus implies the forces cancel or balance each other out. 2. It's actually air resistance. I suggest you read about Aristotle's and Galileo's ...
*October 21, 2013*

**chemistry**

It's an exothermic reaction, since heat is released.
*October 21, 2013*

**MATHS**

By trial and error: Perry's age = 73 Laura's age = 37 Difference of their ages = 36 years Checking: 73-1 = 2(37-1) 72 = 2(36) 72 = 72
*October 21, 2013*

**Pre-Calc**

f(x) = (x^5+3x^3+5x) / (4x^4+2x^2) The only common factor of numerator and denominator is x, but it isn't really necessary to cancel it. i. Vertical Asymptote To get this, we get the limit of x, as f(x) approaches infinity. lim x as f(x)->infinity Or easier way is to ...
*October 18, 2013*

**Math**

1. Yep 2. Yep 3. Yep
*October 18, 2013*

**math**

a. As the problem hinted, Let x = number of weeks Let y = dollars saved For the first equation: you have initially $50, and $10 is added each week. Therefore, at the end of x weeks, the total amount of money you'll have is, y = 50 + 10x For the second equation: same ...
*October 18, 2013*

**Math**

Yes, x can be -13 or 13.
*October 18, 2013*

**maths**

What is the operation? Are we to divide them? And, please clarify the 13^1/2x^2, if it's 13^(1/2 x^2) or 13^(1/(2x^2)).
*October 18, 2013*

**math**

Let x = Mary's age The condition given, in symbols, is x + 10 = 2x - 5 Solving for x, x - 2x = -10 - 5 -x = -15 x = 15 years old hope this helps ;)
*October 18, 2013*

**chem 211**

Write the balanced chemical reaction: C2H4 + H2 -> C2H6 , ΔH = -144 kJ/mol C2H4 Then we get the number of moles of C2H4 using the given mass, 14.6 kg of C2H6. Molar mass, C2H6 = 2*12 + 6*1 = 30 g/mol n,C2H6 = 14.6 * 1000 g / 30 g/mol = 486.67 mol Since the mole ratio ...
*October 18, 2013*

**chem**

Recall that the heat absorbed (+) or released (-) by a substance is given by Q = mc(T2 - T1) where m = mass (g) c = specific heat capacity (J/g-K) T2 = final temperature T1 = initial temperature Note that in the problem, the source of energy or heat came from the alloy. Thus ...
*October 17, 2013*

**math**

Let x = capacity of carton Let y = capacity of cup According to the first statement of the problem, x = 2y According to the second statement, 1.8 = 3y + 2x Now, we have the equations. What we'll do is substitute the first equation to the second: 1.8 = 3y + 2(2y) 1.8 = 3y...
*October 17, 2013*

**math**

Yes.
*October 15, 2013*

**math**

y = 3x - 2(4^x) Yep, the derivative of 3x is 3. Yep, it's true that derivative of 2 is 0, but this is not necessary. Note that 2 is multiplied by 4^x, and does not act as a separate term. Yep, the derivative of 4^x is 4^x(ln(4)). Therefore, y' = 3 - 2*(4^x (ln(4))) or ...
*October 15, 2013*

**Science help! URGENT. Check answers**

1. Yes it's false, because velocity is a vector quantity (which depends on magnitude & direction). 2. Yes, it's acceleration and velocity because both are vector quantities.
*October 15, 2013*

**Geometry**

Note that the sum of interior angles of a triangle is equal to 180 degrees. Therefore, we get the sum of angles R, S and T, then equate to 180: (2x + 10) + (2x + 25) + (x - 5) = 180 Solving, 5x + 30 = 180 5x = 180 - 30 5x = 150 x = 30 degrees Hope this helps~ :)
*October 15, 2013*

**math**

For #s 1 and 2: go to wolframalpha . com and type the equation. For #3: To get the slope, we convert the given equation into the form, y = mx + b where m is the slope and b is the y-intercept. Therefore, -2x - 3y = 5 -3y = 5 + 2x y = 5/(-3) + 2x/(-3) y = (-2/3)x - 5/3 Thus the...
*October 15, 2013*

**school of engineering**

i. Acceleration is the change in velocity over time. a = (v,f - v,o) / t where v,f and v,o are the final and initial velocities respectively, and t is the time. Substituting, a = (100 - 50 km/h)*(1000 m / 1 km)*(1 h / 3600 s) / 10 s a = 1.39 m/s^2 ii. Since the motion is ...
*October 15, 2013*

**Math**

Subtract the final temperature to the initial temperature: 8 - (-3) = 8 + 3 = 11
*October 15, 2013*

**geomrtry**

Recall that the sum of exterior angles of any polygon is equal to 360 degrees. Therefore, we just divide 360 by 40 degrees to get the number of sides: 360/40 = 9 sides hope this helps :)
*October 15, 2013*

**Math, Factoring**

(11x + 5)(11x + 5)
*October 12, 2013*

**Calculus - please help!**

Thank you Mr. Steve! :3
*October 11, 2013*

**Inequalities Answer Check**

1. Yep 2. Yep 3. Yep
*October 10, 2013*

**calculus**

Integral (2x^2-4x-6)dx from 0 to 1 = (2/3)x^3 - 2x^2 - 6x from 0 to 1 = (2/3)(1)^3 - 2(1)^2 - 6(1) - ((2/3)(0)^3 - 2(0)^2 - 6(0)) = 2/3 - 2 - 6 - (0 - 0 - 0) = 2/3 - 8 = 2/3 - 24/3 = -22/3 Hope this helps :3
*October 10, 2013*

**6th grade math**

1. You have to just multiply them, because it says 20% of those 50 students got milk, so 50 * 0.2 = 10 students 2. Yep 3. Yep 4. Yep 5. [Unit ratio] What we'll do here is to get the cost per oz. Thus we divide $1 by 3.6 oz and $2.50 by 11.5 oz, then compare. $1/3.6 = $0....
*October 8, 2013*

**math**

Let x = son's age Let 38-x = Mr. Bellini's age (since the sum of their ages must be equal to 38) Set up the equation using the the second statement: (38 - x) - 4 = 5(x - 4) Solving, 34 - x = 5x - 20 34 + 20 = 6x 54 = 6x x = 9 years old (son's age) 38-x = 29 years ...
*October 8, 2013*

**Calculus**

y = log(8x^2-3x+9) Note that derivative of log(x) = 1/(x*ln(10)) Thus, dy/dx = ( 1/(8x^2-3x+9)*ln(10) ) * (16x - 3) = (16x - 3) / ((8x^2 - 3x + 9)*ln(10)) Hope this helps~ :3
*October 8, 2013*

**Calculus**

f(x) = ax^n f'(x) = a*n*x^(n-1) Substitute the given conditions. f'(3) = a*n*(3)^(n-1) 14 = a*n*(3)^(n-1) f'(6) = a*n*(6)^(n-1) 28 = a*n*(6)^(n-1) We can solve this since there are two equations, two unknowns. From the first equation, we can say that a = 14 / n*(3...
*October 8, 2013*

**Calculus**

y = cos^4(pi*t-20) Note that the derivative of cos(x) = -sin(x) and the derivative of x^n = n*x^(n-1). We'll apply them here, and we'll also use chain rule. dy/dt = 4 * pi * cos^3 (pi*t - 20) * (-sin (pi*t - 20)) Hope this helps~ :3
*October 8, 2013*

**Calculus**

y = log(8x^2-3x+9) Note that derivative of log(x) = 1/(x*ln(10)) Thus, dy/dx = ( 1/(8x^2-3x+9)*ln(10) ) * (16x - 3) = (16x - 3) / ((8x^2 - 3x + 9)*ln(10)) Hope this helps~ :3
*October 8, 2013*

**algebra**

Hi. I answered you previous post and it was almost similar, except that here, the roots must be complex/imaginary so D must be less than zero. Anyway, Recall the formula for discriminant. For a quadratic equation in the general form, ax^2 + bx + c = 0, D = b^2 - 4ac if D = 0...
*October 8, 2013*

**algebra**

Recall the formula for discriminant. For a quadratic equation in the general form, ax^2 + bx + c = 0, D = b^2 - 4ac if D = 0 : real, equal/double root D > 0 : two real, unequal roots D < 0 : two imaginary roots Since we're required to have one real root, we equate D ...
*October 8, 2013*

**pre-Algebra**

17x - 22x = 1/2 -5x = 1/2 x = (1/2)/(-5) x = -1/10
*October 8, 2013*

**calcus**

integral (sec u) du This is pretty tricky, but what we'll do here is multiply both numerator and denominator by (sec u + tan u): = integral (sec u * (sec u + tan u)/(sec u + tan u)) du = integral (sec^2 (u) + sec(u)*tan(u))/(sec u + tan u)) du Then we use substitution. Let...
*October 8, 2013*

**calcus**

integral (tan^3 (x) sec^3 (x)) dx Recall the identity, tan^2 (x) = sec^2 (x) - 1 We substitute it here: = integral (tan(x) * (sec^2 (x) - 1)(sec^3 (x))) dx Let u = sec (x) Thus du = sec(x) tan(x) dx Substituting, = integral (u^2 (u^2 - 1)) du = integral (u^4 - u^2) du = (1/5)*...
*October 8, 2013*

**calcus**

integral cos(x) sin(x) dx We simply use substitution. Let u = sin(x) Thus du = cos(x) dx Rewriting, = integral (u du) = (1/2)*u^2 + C = (1/2)*sin^2 (x) + C Or you may also use substitute the formula sin(2x) = 2sin(x)cos(x) to the original, and then directly integrate. Hope ...
*October 8, 2013*

**Calculus**

Hi. I think Mr. Steve had already answered this before (on your previous post), you may want to check it out. I also answered this on that previous post too, but I'll just copy-paste my answer. s = t^6 * tan(t) - sqrt(t) ds/dt = t^6 (sec^2 (t)) + 6t^5 (tan(t)) - (1/2)(1/...
*October 8, 2013*

**Algebra**

7m + mn + 35 + 5n = m(7 + n) + 5(7 + n) = (m + 5)(7 + n)
*October 8, 2013*

**Algebra**

26(5-x)^2 - 5(5-x)^3 = (5-x)^2 (26 - 5(5-x)) = (5-x)^2 (26 - 25 + 5x) = (5-x)^2 (5x+1)
*October 8, 2013*

**Algebra**

by + ay + bx + ax y(b + a) + x (b + a) Note that you can still factor out the (b + a): (b + a)(y + x) Hope this helps~ :3
*October 8, 2013*

**Math**

What do mean? @_@ Anyway, both sides of equation must be equal. I'll just show the step by step. Note that you should always follow the order of which operation comes first: PEMDAS or Parenthesis - Exponents - Multiplication - Division - Addition - Subtraction But there ...
*October 8, 2013*

**Math**

14 = 50 - 42/(3+4) * 6
*October 8, 2013*

**Algebra**

If only two numbers are involved, Let A and B be real, non-zero numbers. 1) (+)A + (+)B = (+) ? This is always true. 2) (-)A + (-)B = (-) ? This is always true. 3) (+)A - (-)B = (+) ? This is always true. 4) (-)A - (+)B = (-) ? This is always true. 5) (-)A - (-)B = (+) ? This ...
*October 8, 2013*

**Calculus**

s = t^6 * tan(t) - sqrt(t) ds/dt = t^6 (sec^2 (t)) + 6t^5 (tan(t)) - (1/2)(1/sqrt(t))
*October 8, 2013*

**Chemistry**

Assuming the gas is ideal, we can use Boyle's law: P1 * V1 = P2 * V2 where P1 = initial pressure P2 = final pressure V1 = initial volume V2 = final volume Substituting, (1.75 atm)(10.7 L) = P2 * 20 L P2 = 1.75 * 10.7 / 20 P2 = 0.936 atm Hope this helps~ :3
*October 8, 2013*

**Chemistry**

Assuming the gas is ideal, we can use Boyle's law: P1 * V1 = P2 * V2 where P1 = initial pressure P2 = final pressure V1 = initial volume V2 = final volume Substituting, (1.75 atm)(10.7 L) = P2 * 20 L P2 = 1.75 * 10.7 / 20 P2 = 0.936 atm Hope this helps~ :3
*October 8, 2013*

**Chemistry 12**

First we get the molar mass of K2CrO4. To get the molar mass, just get a periodic table, find the individual masses of the elements and add them all based on the chemical formula. Thus, K2CrO4: 2*39.1 + 1*52 + 4*16 = 194.2 g/mol Then recall that molarity is equal to moles of ...
*October 8, 2013*

**Algebra 1**

Let x = time in hours Since their costs must be the same, 100 + 15x = 75 + 17x Solving, 100 - 75 = 17x - 15x 25 = 2x x = 25/2 or 12.5 hours Hope this helps~ :3
*October 8, 2013*

**Algebra 1 (Reiny)**

To solve for a, combine all terms with variables on the left side of the equation, and all constants on the right side of equation. Note that when we transpose a term to the other side, its sign becomes the opposite: 12a - 11 = 9a - 1 12a - 9a = 11 - 1 3a = 10 To get a, divide...
*October 7, 2013*

**Chemistry**

First, you must have the specific substance to know its chemical formula (whether it's H2O, NH3, NaOH, etc.) And then you'll get its molar mass. To get its molar mass, just add the individual masses of the elements in the chemical formula. For instance, MM of H2O: 2*1...
*October 7, 2013*

**Math**

I suppose that "XER" means the domain (all possible values of x) is all real numbers. And the answers there are both...wrong. Anyway, range is the set of all possible values of y (or f(x)). Let's analyze each problem. :) a) f(x) = (x^2+3)^2 Note that x^2 can ...
*October 7, 2013*

**Algebra1 Math**

Let x = time in hours Since their costs must be equal, 800 + 16x = 720 + 21x Solving, 800 - 720 = 21x - 16x 80 = 5x x = 16 hours Hope this helps~ :3
*October 7, 2013*

**maths2**

Formula for discriminant: d = b^2 - 4ac note that if d = 0 : real, equal/double root d < 1 : imaginary roots d > 1 : real, unequal roots 7x2 + 3x + 1 = 0 d = 3^2 - 4(7)(1) d = 9 - 28 d = -19 Thus, it's D. imaginary roots. Hope this helps~ :3
*October 7, 2013*

**math**

There are many ways to do this. Graphing is one. Another way is to convert it to the vertex form: y = a(x-h)^2 + k where (h,k) is the vertex and the axis of symmetry is x=h. Thus, y = -4x^2 - 24x - 36 y = -4(x^2 + 6x) - 9 y = -4(x^2 + 6x + 9) - 9 + 9 y = -4(x+3)^2 Thus, V(-3,0...
*October 7, 2013*

**Taking Time to Thank**

OMG I'm not really a homework helper, it's just like my pastime answering some questions that I think I know. :3 But you're welcome and I'm very happy I could be of help! (◕‿◕✿)
*October 7, 2013*

**Chemistry**

First we get the mass of NH3 (ammonia) in the concentrated NH3 solution, by using the relationship between density, mass and volume: d = m/V 0.88 = m/28.2 m = 24.816 g Since ammonia is only 28% of this mass, m,NH3 = 24.816 * 0.28 m,NH3 = 6.9485 g NH3 Then we change this to ...
*October 7, 2013*

**chemistry**

Total mass of solution = 5 + 95 = 100 grams Recall that the formula for calculating the heat absorbed or released is given by Q = mc(T2 - T1) where m = mass c = specific heat capacity (T2 - T1) = change in Temperature Substituting, Q = 100 * 1.1 * 10 Q = 1100 cal Hope this ...
*October 7, 2013*

**Calculus, please check my answers!**

1. Yep, the limit approaches infinity 2. Nope, the limit is zero. lim (2^x+x^3)/(x^2+3^x) as x-> infinity We'll use L'Hopital's rule here (I hope it was already taught in your class). It is used when you get the form 0/0 or infinity/infinity when the x value is ...
*October 7, 2013*

**Algebra**

a. Let x = amount of 10% salt solution in gallons Since the total volume must be equal to 5, Let 5-x = amount of 25% salt solution in gallons We'll do a salt balance here. Thus, the equation would be, 0.1x + 0.25(5-x) = 0.2(5) b. Solving, 0.1x + 0.25(5-x) = 0.2(5) 0.1x + 1...
*October 7, 2013*

**maths2**

D. No solution
*October 6, 2013*

**maths**

What's the question? If the question says, which of the following points satisfies the equation, then there is no answer. Probably there is a typo...
*October 6, 2013*

**chemistry**

Recall the formula M1 * V1 = M2 * V2 where M1 = initial concentration M2 = final concentration V1 = initial volume V2 = final volume Substituting, 4.7 * 4 = M2 * 45 M2 = 4.7 * 4 / 45 M2 = 0.418 M Hope this helps :3
*October 6, 2013*

**math**

It's hard to show here the actual graph so I'll just tell you what to do. There are plenty of ways to graph them, but this is, for me, the simplest: 1. First, find the x- and y-intercepts. To the x-intercept, let y = 0 and solve for x. To find the y-intercept, let x = ...
*October 6, 2013*

**math**

Recall that the circumference of a circle is equal to C = pi*d where d is the diameter. First we get the circumference, then we multiply it by the number of revolutions, which is 20: C = 3.14 * 65 C = 204.1 cm (this is only equal to 1 revolution) Therefore, total distance ...
*October 5, 2013*

**Calculus**

Req'd: area bounded by y = x and y = 2*sqrt(x) First thing to do here is to find their points of intersection, so we'll know the bounds. We can do it algebraically or graphically. To find algebraically the points of intersection, we just use substitution. Since y = x, ...
*October 4, 2013*

**Math PLEASE HELP!!!**

letter D is false. For instance, 90 is divisible by 6 and 10, but not divisible by 60.
*October 2, 2013*

**MATH**

Let x = amount of John's or Matt's money Set up the equation. According to the first statement, x - 130 = 3(x - 480) Solve for x: x - 130 = 3x - 1440 x - 3x = -1440 + 130 -2x = - 1310 x = $ 655 Hope this helps~ :3
*October 2, 2013*

**calculus**

d/du ( 1/(2u^2 - 1)^2 ) d/du ( (2u^2 - 1)^-2 ) = -2(4u)(2u^2 - 1)^-3 = -8u / (2u^2 - 1)^3 Hope this helps~ :3
*October 2, 2013*

**chemistry**

Standard Temperature = 273 K or 0 deg Celsius Standard Pressure = 1 atm STP is needed to have a reference value in order to make comparisons with different sets of data values.
*October 2, 2013*

**geometry**

Note that point B is in segment AC, therefore we can say that the sum of lengths of AB and BC is equal to AC, or AB + BC = AC Substituting, (2x - 1) + (3x + 5) = 24 5x + 4 = 24 5x = 20 x = 4 Thus, AB: 2(4) - 1 = 7 units Hope this helps~ :3
*October 2, 2013*

**Intermediate Algebra**

sqrt(5x^2 - 3x) = 2x First thing to do is to square both sides of the equation, then solve for x: [sqrt(5x^2 - 3x)]^2 = (2x)^2 5x^2 - 3x = 4x^2 x^2 - 3x = 0 x(x - 3) = 0 x = 0 x = 3 Then to check if it really satisfies the original equation, substitute the x values back to the...
*October 2, 2013*

**Intermediate Algebra**

sqrt(y + 10) = y - 2 First thing to do is to square both sides of the equation, then solve for x: y + 10 = (y - 2)^2 y + 10 = y^2 - 4y + 4 0 = y^2 - 5y - 6 0 = (y - 6)(y + 1) y = 6 y = -1 Now to check, substitute the x values back to original equation. y = -1: sqrt(-1 + 10...
*October 2, 2013*

**math**

15y^7 / 5y^4 = (15/5) * (y^7 / y^4) = 3y^3
*October 2, 2013*

**Intermediate Algebra**

sqrt(5x - 4) = 6 First thing to do is to square both sides of the equation, then solve for x: [sqrt(5x - 4)]^2 = 6^2 5x - 4 = 36 5x = 36 + 4 5x = 40 x = 8 Hope this helps~ :3
*October 2, 2013*

**math**

10^1 - 10^0 = 10 - 1 = 9
*October 2, 2013*

**math**

(a+b)^9 / (a+b)^9 = 1
*October 2, 2013*

**math**

(ab^8)*(a^5)*(b^6) To multiply, just add the exponents of those terms with the same base: = a^(1+5) * b^(8+6) = (a^6)(b^14) Hope this helps~ :3
*October 2, 2013*

**Intermediate Algebra**

3 squareroot(13) + 7 squareroot(13) Note that you can only add or subtract terms with radicals if they have the same radicand (expression inside the radical sign) and same root (square root, cube root, fourth root, etc.) Therefore, it becomes = 10 squareroot(13) Hope this ...
*October 2, 2013*

**8th Grade Physical Science**

Recall that the formula for density is d = m/V where m is the mass and V is the volume. Substituting, d = 30/7500 d = 0.004 g/cm^3 Hope this helps~ :3
*October 1, 2013*

**math**

Note that 0.7 is also 7/10. The given are 1/4, 7/10, 3/5 What you can do here is first find the LCD (Least Common Denominator) or the smallest number where it is divisible by 4, 10 and 5. By looking, we can say that the LCD = 20. Then we convert each fraction at which their ...
*October 1, 2013*

**Math**

134n + 55
*October 1, 2013*

**Math**

We let the unknowns using variables: Let n = number of quarters Let k = number of dimes Note that the sum or total of quarters and dimes is 47. Therefore, we can say that n + k = 47 Since we need to find the number of dimes (which is k) in terms of umber of quarters (that is n...
*October 1, 2013*

**Math**

q + 49
*October 1, 2013*

**Math**

Let w = width Let 2w - 5 = length (according to first statement) Then we set up the equation. Recall that the perimeter of a rectangle is equal to P = 2L + 2W where L is length and W is width. Thus, 26 = 2(2w - 5) + 2w We solve for x: 26 = 4w - 10 + 2w 26 = 6w - 10 36 = 6w w...
*October 1, 2013*

**Math**

Note that the difference between two consecutive integers is equal to 1. Thus, Let x = first number Let x+1 = the second number Then we set up the equation. It says in the problem that their sum is 59, so x + x + 1 = 59 Finally we solve for x: 2x + 1 = 59 2x = 59 - 1 2x = 58 (...
*October 1, 2013*