I'm not sure how to do this. Help please?

The ratio of the height of two similar pyramids is 4:7. The volume of the smaller pyramid is 1,331cm, to the nearest whole numbe

IRISSAK [1]

Answer:

The volume of the larger pyramid is equal to $7,133\ cm^{3}$

Step-by-step explanation:

step 1

Find the scale factor

we know that

If two figures are similar, then the ratio of its corresponding sides is equal to the scale factor

Let

z----> the scale factor

In this problem, the ratio of the height is equal to the scale factor

$z=\frac{4}{7}$

step 2

Find the volume of the larger pyramid

we know that

If two figures are similar, then the ratio of its volumes is equal to the scale factor elevated to the cube

Let

z----> the scale factor

x----> volume of the smaller pyramid

y----> volume of the larger pyramid

$z^{3}=\frac{x}{y}$

we have

$z=\frac{4}{7}$

$x=1,331\ cm^{3}$

substitute

$(\frac{4}{7})^{3}=\frac{1,331}{y}\\ \\(\frac{64}{343})=\frac{1,331}{y}\\ \\y=343*1,331/64\\ \\y=7,133\ cm^{3}$

8 0

3 years ago

10, 13, 19, 28, 40 repeating patterns

photoshop1234 [79]

Each number goes up by 3. 13-10=6, 19-13=9, 40-28=12, etc. The next number would be 40+15=55

6 0

3 years ago

Help me plz and ty<br> :) :)

Ivahew [28]

Answer:

1.

40 students chose papa johns and 24 did not

2. 14 students chose dominos and 10 chose pizza hut

Step-by-step explanation:

1. set up a proportion like 5/8 x x/64 and cross mutliply like 8 times x and 5 times 64

4 0

3 years ago

Write the equation of the parabola that has its x-intercepts at (1+<img src="https://tex.z-dn.net/?f=%5Csqrt%7B5%7D" id="TexForm

VladimirAG [237]

Answer:

$y=2x^2-4x-8$

Step-by-step explanation:

<u>Factored form of a parabola</u>

$y=a(x-p)(x-q)$

where:

p and q are the x-intercepts.
a is some constant.

Given x-intercepts:

(1+√5, 0)
(1-√5, 0)

Therefore:

$\implies y=a(x-(1+\sqrt{5}))(x-(1-\sqrt{5}))$

$\implies y=a(x-1-\sqrt{5})(x-1+\sqrt{5})$

To find a, substitute the given point (4, 8) into the equation and solve for a:

$\implies a(4-1-\sqrt{5})(4-1+\sqrt{5})=8$

$\implies a(3-\sqrt{5})(3+\sqrt{5})=8$

$\implies4a=8$

$\implies a=2$

Therefore, the equation of the parabola in factored form is:

$\implies y=2(x-1-\sqrt{5})(x-1+\sqrt{5})$

Expand so that the equation is in standard form:

$\implies y=2(x^2-x+\sqrt{5}x-x+1-\sqrt{5}-\sqrt{5}x+\sqrt{5}-5)$

$\implies y=2(x^2-x-x+\sqrt{5}x-\sqrt{5}x+\sqrt{5}-\sqrt{5}+1-5)$

$\implies y=2(x^2-2x-4)$

$\implies y=2x^2-4x-8$

6 0

1 year ago

Solve for x..........................

Lelechka [254]

Answer:

3

Step-by-step explanation:

If your talking about the x where it says 3x in, then

3x = 9

x = 3

4 0

3 years ago