SOLUTION: Find the x-intercepts. y = x^2 + 2x – 15 Please show the step-by-step process to complete this problem. Thank you.

Algebra ->  Quadratic Equations and Parabolas  -> Quadratic Equations Lessons  -> Quadratic Equation Lesson -> SOLUTION: Find the x-intercepts. y = x^2 + 2x – 15 Please show the step-by-step process to complete this problem. Thank you.      Log On


   

Question 89117: Find the x-intercepts.
y = x^2 + 2x – 15
Please show the step-by-step process to complete this problem. Thank you.
Answer by tutor_paul(519) About Me  (Show Source):
You can put this solution on YOUR website!
y=x%5E2%2B2x-15
The x intercepts are the points where y=0. So set y equal to zero in the equation and solve for x:
0=x%5E2%2B2x-15
Factor this to get your values of x:
x%5E2%2B2x-15=0
%28x%2B5%29%28x-3%29=0
So now you have 2 factors, (x+5) and (x-3). Since their product is equal to zero, each individual factor can be equated to zero. Then, it is easy to solve for x:
x%2B5=0
highlight%28x=-5%29
x-3=0
highlight%28x=3%29
Good Luck,
tutor_paul@yahoo.com