Question

The area of a rectangle is given by x2 - 12x + 35. Determine the length and breadth in

terms of x. Hence, determine the length and breadth if x = 20.
(3)

Answer 1

`x+7; x+5; 27; 25`

Explanation:

First of all, we need to write
`x^2+12x+35` as a product. The easiest way is to find a pair of numbers whose product is 35 and sum is 12. Looking at the product, you notice it's 7 and 5, which added together indeed give 12.

The two side length are thus
`x+7` and
`x+5`.

In the specific case, when
`x=20` the two sides measures 27 and 25.