Question

The value of the solid's surface area is equal to the value of the solid's volume. Find the value of x. We know the length is 9 and the width is 4, but the height is x

Answer 1

Given:

The value of the solid's surface area is equal to the value of the solid's volume.

Length(l) = 9 units

width(b) = 4 units

Height(h) = x units

To find:

The value of x.

Solution:

Solid's surface area is

$Area=2(lb+bh+hl)$

$Area=2(9\times 4+4\times x+x\times 9)$

$Area=2(36+4x+9x)$

$Area=2(36+13x)$

$Area=72+26x$

Volume of solid is

$Volume=l\times b\times h$

$Volume=9\times 4\times x$

$Volume=36x$

Solid's surface area = Volume of solid

$72+26x=36x$

$72=36x-26x$

$72=10x$

Divide both sides by 10.

$7.2=x$

Therefore, the value of x is 7.2.