Question

Part

Answer 1

The last term is 63 so 3 might be a zero of the function;-

f(3) = 27 - 7*9 - 3*9 +63 = 27 - 63 - 27 + 63 = 0  so 3 is a zero and

therefore (x - 3) is a factor  of the volume function.

Long division  of the expression by x - 3 gives the quotient:-

x^2 + 4x - 21

Factoring this:-

= ( x + 7)(x - 3)

So the dimensions of the box are, x-3, x-3 and x+7  answer.