SOLUTION: one x-intercept for a parabola is at the point (1,0). use the factor method to find the other x-intercept for the parabola defined by this equation: y=4x^2+4x-8

Algebra ->  Quadratic-relations-and-conic-sections -> SOLUTION: one x-intercept for a parabola is at the point (1,0). use the factor method to find the other x-intercept for the parabola defined by this equation: y=4x^2+4x-8      Log On


   

Question 390243: one x-intercept for a parabola is at the point (1,0). use the factor method to find the other x-intercept for the parabola defined by this equation: y=4x^2+4x-8
Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!


Hi,        

factoring to find x when y = 0

 4x^2 + 4x - 8 = 0

 4[x^2 + x - 2} = 0

 4[(x-1)(x+2)]= 0 Note:SUM of the inner product(-x) and the outer product(2x) = x

 (x-1)(x+2)= 0

 (x-1)= 0

    x = 1  already determined:  Pt(1,0) named an x-intercept

 (x+2)= 0

    x = -2  Pt(-2,0) the other x-intercept