if x^2+2x-15=(x+r)(x+s) for all values of x one possible value of for r-s is?

Answer 1

x^2+2x-15=(x+r)(x+s)
(x+5)(x-3) = (x+r)(x+s)

so r = 5 and s = -3

r - s
= 5 - (-3)
= 8