Relax

Respuesta :

Answer:

x^2-x-90=0     x^2-10x+9x-90    x(x-10)+9(x-10)

(x+9)(x-10)=0

Solutions are 0-9=-9 and 0+10=10.

10-9=1= a+b

Step-by-step explanation:

Answer:

a + b = 1

I hope this helps!