Respuesta :

Given

a cuboid with length, width, height dimensions 5, 6, x

Find

the value of x that makes the numerical value of the total surface area equal to the numerical value of the volume

Solution

The volume is given by

... V = L·W·H = 5·6·x = 30x

The area is given by

... A = 2(L·W + H(L+W)) = 2(5·6 +x(5+6)) = 2(30 +11x) = 60 +22x

When these are equal, we have

... 30x = 60 +22x

... 8x = 60

... x = 7.5

The desired value of x is 7.5.