Respuesta :

A= 1/2bh
60= 1/2(X)(X+7)
60= 1/2 x^2+7x
Multiply both sides by 2 to get rid of 1/2
120= x^2+7x
X^2+7x-120=0. (
)X+15)((X-8)
X+15=0. X-8=0
X=-15. X=8
Can't be negative so Answer is 8

Check 60= 1/2(8)(15)
60= 4(15)
60=60