Question

The area of a rectangle is 28 square inches. The length is 8 more than thrice the width. How do you find the length and the width?

Answer 1

Width = `2`
Length = `14`

Explanation:

Length: `L = 3x + 8`
Width: `W=x`

Area of Rectangle = `LW`
`28 = (3x+8)x`
`28 = 3x^2 + 8x`
`0 = 3x^2 + 8x - 28`
`0 = (3x + 14 )(x - 2)`

`3x + 14 = 0 -> x = -14/3`
But Width can't be negative.

`x - 2 = 0 -> x = 2`
So Width is `2` and Length is `3(2)+8 = 14`