Hi
y=2x^2+4x-6 |determining the x-intercepts (when y=0)
2x^2+4x-6 = 0
factoring
(2x -2)(x+3)=0 Note:SUM of the inner product(-2x) and the outer product(6x) = 4x
(2x -2)=0 x = 1 x-intercept at Pt(1,0)
(x-3)=0 x= -3 x-intercept at Pt(-3,0)
Note: the vertex form of a parabola,
where(h,k) is the vertex
y=2x^2+4x-6 |completing the square to put into vertex form
y = 2(x^2+2)-6
y= 2[(x+1)^2 -1] -6
y= 2(x+1)^2 -8 Vertex is at Pt(-1,-8) parabola opens upward (2>0)
