Question

An open box is made from a square piece of metal by cutting out a 4 inch square from each corner and turning up the sides. Find the area of the original square if the box is to contain:
A) 16 cubic inches
And
B) 400 cubic inches

Answer 1

let the piece of metal be x inches by x inches

base of box is (x-8) by (x-8) , where x

so
4(x-8)(x-8) = 16
x^2 - 16x + 64 = 4

(x-6)(x-10) = 0
x = 6 or x = 10 , but remember x > 8

so the original piece of metal was 10 inches by 10 inches

You try B