Respuesta :

We are given a polynomial representing the area of a barnyard that is  4x2 + 8x - 21. A rectangle's area is equal to length multiplied by the width which means we can use factoring.

 4x2 + 8x - 21
 (2x - 3 ) (2x + 7)

we can countercheck this to verify the polynomial.

In this case, the dimensions are 
 2x - 3  and 2x + 7.