Jeffrey Z. answered • 12/10/14

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1. X-intercepts on the graph correspond to zeros of the function, so you need to solve F(x)=2(x+1)(x-2)=0. So the two answers are -1 and +2.

2. Using the FOIL method to multiply polynomials, Y=(x+1)(x-3)=x^2-2x-3.

3. The function is a downward-opening parabola with a vertex at (-3,1). The line of symmetry passes vertically through the vertex, and is therefore x=-3.

4. Plug each x into the function, and the only one that comes up with the proper y is (1,1): 1=-(1^2)+4(1)-2.