Saturday

February 13, 2016
Total # Posts: 37,644

**math**

work = force * distance force = weight so, what do you think?
*February 10, 2016*

**math**

none, as long as you are talking about the longer base of a trapezoid. Often, though, b refers to the base of a triangle. Also, it may be the shorter base of a trapezoid.
*February 10, 2016*

**maths**

for dimensions x,y,z, bottom: xy sides xz and yz, two of each Now just plug in your numbers
*February 10, 2016*

**math**

reflect: (x,y) -> (-x,y) left: (x,y) -> (x-3,y) down: (x,y) -> (x,y-6) So, for all three, (x,y) -> (-x,y) -> (-x-3,y) -> (-x-3,y-6) (4,2) -> (-7,-4) and so on
*February 10, 2016*

**math**

the 2nd translation takes (x-6,y+2) -> (x-6+3,y+2+1) = (x-3,y+3)
*February 10, 2016*

**Geometry**

if the angle is x , then tan(x) = .284 x = arctan(.284)
*February 10, 2016*

**Math**

100/(b+24) what do you get for the other?
*February 10, 2016*

**Math**

(1 2/3):(5/4) = (5/3):(5/4) = 4:3
*February 10, 2016*

**math**

r^3 = -243/72 = (-9*27)/(9*8) r = -3/2 a(-3/2)^2 = 72 a = 32 S10 = 32(r^10-1)/(r-1) = -11605/16
*February 10, 2016*

**Onto functions**

Read the introduction in wikipedia explaining the difference between range and codomain. For example, if g:R->R g(x)=x^2, then the codomain is all of R, but the range (image) is [0,∞) For this problem, g is onto, since both the codomain and the image are [1,∞). ...
*February 10, 2016*

**Cal 2**

However, just so you get to use your calculus to analyze the frustrum, just think of it as a stack of thin discs of thickness dx: v = ∫πr^2 dx where r=y=3x v = ∫[3,5] π(3x)^2 dx = 294π Or, as a bunch of nested shells, it gets a bit more complicated, ...
*February 10, 2016*

**math**

read amount read rate mrate = rate/12.0 bal = amount * (1+mrate)^4 that last expression might vary, depending on the language: (1+mrate)**4 pow(1+mrate,4)
*February 10, 2016*

**algebra**

y-0 = 2(x-0) y = 2x
*February 10, 2016*

**math**

Not quite sure how to parse that 2nd sentence, but let's just work with the height of the tower above his eye level. Draw a diagram and review the cot function. You will see that if the height is h, h cot28° - h cot35° = 50 Now find h and add 1.70
*February 10, 2016*

**angle relationships**

90° - 48°26'8"
*February 9, 2016*

**Shresta**

cosx sinx = √2 cosx sinx = √2 sorry - cannot happen However, cosx-sinx = √2 (1/√2 cosx - 1/√2 sinx) = √2 sin(π/4 + x)
*February 9, 2016*

**Calculus**

Hmm. In that case, you need times where both hands are exactly on numbers. So, there are 11 such times, exactly on hours. At 2:00, say if you switch hands the hour hand will be on 12 and the minute hand will be on 2, so the time is 12:10. Now, on a real clock, the hour hand ...
*February 9, 2016*

**Math**

9m+6n = 3 8m+6n = 6 subtract and you have m = -3 That means n = 5
*February 9, 2016*

**Math**

If you mean quadratic regression, I'd google the topic and read some of the articles. Hard to believe such a complicated process would be on a test under limited time. At any rate, if you do find a quadratic f' = ax^2+bx+c, then clearly f = a/3 x^2 + b/2 x^2 + cx + d ...
*February 9, 2016*

**Math**

.84^n = .25
*February 9, 2016*

**math**

I assume we are talking about the 1st terms of the sequences. well, shucks, 32=2^5 1*2*4*8*16 too big 1/2 * 1 * 2 * 4 * 8 = 32 a= 1/2 r = 2 S19 = 19/2 (a + 18d) but, a+9d = 2 so, 2a+18d = 4 so, a+18d = 4-a = 7/2 S19 = (19/2)(7/2) = 133/4
*February 9, 2016*

**math**

(7+x)/12 = 4
*February 9, 2016*

**Geometry**

In fact, it's not drawn here at all. However, opposite angles are equal successive angles are supplementary.
*February 9, 2016*

**programming**

well, the hardest part is picking off the digits of the number. That is easily done by taking the remainder when dividing by 10. So, if the number is n, this can be achieved by the following loop: int n,d; d=0; while (n > 0) { d = n%10; #now you have the ones' digit #...
*February 9, 2016*

**math :) website**

You're Welcome.
*February 9, 2016*

**math :) website**

This website should help you. http://www.purplemath.com/modules/meanmode.htm
*February 9, 2016*

**I NEED HELP WITH THIS. PLZ**

https://www.connexus.com/content/media/595718-3162012-80436-AM-754148529.png FOR #1
*February 9, 2016*

**Math**

If they start with amounts c and s (in cents), then we are told c+80 = 0.80s s+70 = 1.50c now just solve for c and s.
*February 9, 2016*

**physics**

this is discussed here: http://hyperphysics.phy-astr.gsu.edu/hbase/electric/elesph.html
*February 9, 2016*

**salag national high school**

There are 5! = 120 ways to arrange 5 flags. Since 2 of them cannot be distinguished from each other, divide that number by 2.
*February 9, 2016*

**math**

geez - just plug your numbers into the formula: S11 = 11/2 (2*2+10*3)
*February 9, 2016*

**math**

each year the car is worth 90% of its prior value, so 600000*0.9^4 That's some car!! Sure it was not a house or a yacht?
*February 9, 2016*

**GYAN**

Until you say how many they lost, no way to tell. However, if you know how many total games they have played, the fraction won will be 13/total then convert that to a percent.
*February 9, 2016*

**phisics**

clearly the flight lasted 0.5 seconds. So, how far did it fall in 0.5s? s = 1/2 at^2
*February 9, 2016*

**math**

Draw a diagram. If the pole has height h, then h cot36° + h cot42° = 50 h = 20.1 Now, the wires have lengths 20.1/sin36° and 20.1/sin42°
*February 9, 2016*

**Calculus 2**

It doesn't really matter which variable is used, since the boundary changes in either direction. Cleverly enough, the hyperbola intersects the two lines at (√(7/2),√14) and (√14,√(7/2). So, a = ∫[0,√(7/2)] (2x)-(x/2) dx + ∫[√...
*February 9, 2016*

**ALGEBRA**

one is: 2.00x + 1.50y = 20.00
*February 9, 2016*

**computer programing**

assuming that the code being reused is well structured, it will contribute to the structure of the whole program. Plus, if the used code has been tested, it will shorten the development time, since known good code is being used.
*February 9, 2016*

**Calc**

Nope. That's way too fast. How long does it take to fall to a height of -250m? 35t - 4.9t^2 = -250 t = 11.56 Now, v = 35 - 9.8t = -78.26
*February 9, 2016*

**Math**

well, you could factor out the 2, making it (2±i√10)/7
*February 8, 2016*

**Calculus**

Something missing from this answer? http://www.jiskha.com/display.cgi?id=1454557669
*February 8, 2016*

**math**

for x miles, you want 70+.40x < 50+.50x 20 < .1x 200 < x so, at 200 miles, A starts to be cheaper.
*February 8, 2016*

**math**

0.1x <= 5.00 Suppose pencils cost 10 cents each. If you only have $5.00 to spend, how many pencils can you buy?
*February 8, 2016*

**calculus 1**

#2 more properly, °F/mo otherwise, they look good.
*February 8, 2016*

**equation**

but you could start with d = 2m
*February 8, 2016*

**equation**

what a wimp.
*February 8, 2016*

**calc**

what is a negative line? A vertical line means a sudden, probably discontinuous) jump in value.
*February 8, 2016*

**Math**

(3/4)(6) = 18/4
*February 8, 2016*

**Math**

gals = (gals/min)(min) a = 500m
*February 8, 2016*

**Science**

well, 1 square means 3 feet. Other than that, I have no idea how many squares you need. Only one, if you want to draw a 3' distance.
*February 8, 2016*

**Physics**

V = k/P That is, VP = k is constant so, you want P such that 15P = (2)(1065)
*February 8, 2016*

**Physics**

since time = distance/speed, 1/(2-1) + 1/(2+1) = 1/1 + 1/3 = 4/3 Looks like (D) to me
*February 8, 2016*

**Math**

If we let the length of a whole board be 1, then for n boards, we have 2/5 n = 4 n = 10
*February 8, 2016*

**maths**

a loss of 10% means that each year the value is 90% of what it was before.
*February 8, 2016*

**Grade 5 math**

express all distances in the sam units: 400m = 400m .45km = 450m 40,000mm = 40m Now what do you think?
*February 8, 2016*

**math**

floor: 12*10 long walls: 2(12*8) short walls: 2(10*8) Now add 'em up.
*February 8, 2016*

**Math**

29.95/1.02 = ?
*February 8, 2016*

**physics**

see related questions below
*February 8, 2016*

**Math**

1B Can you not tell that by looking at the figure? 2B a square is a rectangle with 4 equal sides. 3B just look at the letters, keeping them in the same order.
*February 8, 2016*

**Math**

apparently her notation is ^. for * meaning multiply. Trés strange.
*February 8, 2016*

**math**

First, that's pi not pie!!! Just start subtracting 2pi from your angle until the result is between 0 and 2pi. 3pi - 2pi = pi we have a winner!
*February 8, 2016*

**maths**

When asking how much one value is than another, you just subtract. If I ask How much bigger 10 is than 3, you do 10-3=7. So, (-39)-(-98) = -39+98 = 59
*February 8, 2016*

**math**

well, did you try actually verifying it? (5/8)(-3/5) + (1/16)(-3/5) = -15/40 - 3/80 = -33/80 3/16 - 3/5 = 15/80 - 48/80 = -33/80 I guess your answer is correct.
*February 8, 2016*

**Math**

If there are x lbs, each one gets x/3 so x >= 10.5 x/3 >= 3.5
*February 8, 2016*

**Algebra**

105 mi/hr = 154 ft/s So, it takes 60.5/154 seconds
*February 8, 2016*

**Math**

the independent variable is the one which you can set to whatever you want: in this case, the number of students. Since there is a fixed cost for each student, the cost depends on the number of students.
*February 8, 2016*

**MATH**

5x + 4.20(26-x) = 4.80*26
*February 8, 2016*

**MATH**

stop posting problems which refer to a pictures we cannot see.
*February 8, 2016*

**math**

3^x * 5^x + 1=20 (3*5)^x = 19 15^x = 19 x = log1519
*February 8, 2016*

**Math**

hard to say, with no picture to see.
*February 8, 2016*

**Math**

area grows as the square of the sides. So, the areas are in the ratio (2/3)^2 = 4/9
*February 8, 2016*

**Math**

If you mean of a circle, it is that portion of a circle subtended by a central angle. That is, if two radii are drawn, the sector is the area between them.
*February 8, 2016*

**Maths**

(22^3 * 7/8)/(π/6 * .5^3) ≈ 142,353
*February 8, 2016*

**math**

p(w) = 7+2w
*February 8, 2016*

**Calculus (double integral) PLEASE HELP!**

This exact transformation is discussed on pp 3-5 of http://math.etsu.edu/multicalc/prealpha/Chap4/Chap4-4/printversion.pdf
*February 8, 2016*

**Math**

p(t) = 157354 * 2^t
*February 8, 2016*

**math**

One way is elimination, where you multiply the equations to enable addition to eliminate one variable: 6x+4y = -36 -6x+15y = -78 now if you add them up you get 19y = -114 Thus, having y, you can now get x from either equation.
*February 8, 2016*

**math**

the area of the border is (500)(130)-(500-2*25)(130-2*25) = 29000 cm^2 Now you can find the cost
*February 8, 2016*

**trigonometry**

Remember the Pythagorean Theorem? The distance d is d^2 = 200^2 + 60^2
*February 7, 2016*

**Calculus (Jacobian question)**

This type of problem is discussed on pages 3-5 at http://math.etsu.edu/multicalc/prealpha/Chap4/Chap4-4/printversion.pdf
*February 7, 2016*

**Math**

mass of pure gold would be 5*18*4 cm^3 * 19.3 g/cm^3 = 6948g so, what do you think?
*February 7, 2016*

**calculus**

∫ x^3/√(3x^2-5) dx x = √(5/3) secθ 3x^2-5 = 5tan^2θ dx = √(5/3) secθ tanθ dθ and the integral becomes ∫ √(5/3)^3 sec^3θ/(√5 tanθ) √(5/3) secθ tanθ dθ = 5/9 √5 ∫sec^4&#...
*February 7, 2016*

**physics**

oops. the horizontal speed is 33.437 cos20° make that fix...
*February 7, 2016*

**physics**

h(t) = vt - 1/2 g t^2 3.5v - 4.9*3.5^2 = -20 v = 11.436 That v is the vertical speed at takeoff. So, the entire initial speed is 11.436/sin20° = 33.437 Use that speed and d = vt to get the horizontal distance traveled. d = 33.437 * 3.5 = 117.028
*February 7, 2016*

**Precalculus**

Huh? Forget your Algebra I? Anyway, just type in your function at wolframalpha.com
*February 7, 2016*

**Trigonometry**

Draw a diagram, and you will see that x cot14° + x cot18° = 55 x = 55/(cot14° + cot18°)
*February 7, 2016*

**math**

.42
*February 7, 2016*

**Algebra**

u = kp^3/d
*February 7, 2016*

**Algebra**

add up the value of the parts: 8.40x + 14.70(70-x) = 14.61*70 Expect a value of nearly zero for x, since the price of the mix is very close to the price of the Mexican coffee.
*February 7, 2016*

**Calculus**

The paraboloids intersect along an ellipse 3x^2+2y^2 = 6 So, the volume is (using symmetry) v = 4∫[0,√2] ∫[0,√((6-3x^2)/2)] (6-x^2-y^2)-(2x^2+y^2) dy dx = 3π√6
*February 7, 2016*

**math**

you are right
*February 7, 2016*

**Math**

You are correct.
*February 7, 2016*

**Numericals**

v = √2as = √(2*9.8*15) = 17.146 m/s Since the ball's energy PE = mgh, if it loses 40% of its energy, it will lose 40% of its height, so it will bounce to 9 m. Or, since PE becomes KE just before impact, KE = 1/2 mv^2 The rebound velocity will be .6 * 1/2 m*17....
*February 7, 2016*

**calculus**

see related questions below.
*February 7, 2016*

**radicals**

just multiply roots like anything else. If a square root contains a perfect square, like 16 or 49, you can factor the 4 or 7 out of the root. For this problem, √8(√(9ab)/√(3b) + √(27a)) 2√2 (√(9ab/3b) + 3√(3a)) 2√2 (√(3a...
*February 7, 2016*

**calculus**

a = (90-30)/10 = 6 km/hr-s s = 1/2 at^2 = 3 km/hr-s * (10s)^2 = 300 km-s/hr = 300 km-s/hr * 1hr/3600s = 300/3600 km = 1/12 km or, since you want to use calculus, a = 6km/hr-s = 6km/hr-s * 1hr/3600s = 1/600 km/s^2 so, a(t) = 1/600 v(t) = 1/600 t s(t) = 1/1200 t^2 s(10) = 100/...
*February 7, 2016*

**math**

if compound interest, 400(1+r)^4 = 480 (1+r)^4 = 1.2 r = .0466 Is your new r (r + .02)=.0666 or is it 9*1.02 = .0475 ?? Do a similar calculation if simple interest.
*February 7, 2016*

**Math**

f(x) = √(x-2) You know that the domain of √x is x>=0. So, you need x-2 >= 0 Not too hard, eh?
*February 6, 2016*

**maths**

well, sin(x) = 125/250 = 1/2 look familiar?
*February 6, 2016*