You can put this solution on YOUR website! should be x = 7
factor the quadratic equation as follows:
(x-a)*(x+b) = 0
you want an a and a b such that b-a = 2
look at the factors of a*b that equal 63.
you get:
63*1
21*3
7*9
looks like 7 and 9 will do it because 9-7 = 2
set b = 9 and a = 7 and you get:
(x-7) * (x+9) = 0
results in x = 7 or x = -9
positive x-intercept is 7.
graph of the equation of x^2 + 2x - 63 confirms it as shown below:
