Respuesta :

mhanifa

Answer:

  • 7 m

Step-by-step explanation:

Let the width is w and the length is w + 5.

The area is 84:

  • w(w + 5) = 84
  • w² + 5w - 84 = 0
  • w² + 12w - 7 w - 84 = 0
  • w(w + 12) - 7(w + 12) = 0
  • (w - 7)(w + 12) = 0
  • w = 7 is the only positive root

Otras preguntas