SOLUTION: I need to know the vertex, axis of symmetry, roots, domain, range for the following problem Y=-2(x+3)(x-1) i also need to know if it opens up or down and if you can graph it that

Algebra ->  Quadratic-relations-and-conic-sections -> SOLUTION: I need to know the vertex, axis of symmetry, roots, domain, range for the following problem Y=-2(x+3)(x-1) i also need to know if it opens up or down and if you can graph it that      Log On


   

Question 911619: I need to know the vertex, axis of symmetry, roots, domain, range for the following problem
Y=-2(x+3)(x-1)
i also need to know if it opens up or down and if you can graph it that would be greatly appreciated.
Found 2 solutions by josgarithmetic, ewatrrr:
Answer by josgarithmetic(39617) About Me  (Show Source):
You can put this solution on YOUR website!
The graph opens downward, since just looking at the expression shows you the coefficient on x%5E2 is negative. Symmetry axis is between the roots in the exact middle and you can read the roots directly from the quadratic expression because it is given in its factored form. Symmetry axis is the middle of x=-3 and x=1.

Domain, range, and vertex will best be found through converting into standard form as discussed here: http://www.algebra.com/my/Completing-the-Square-to-Solve-General-Quadratic-Equation.lesson?content_action=show_dev

Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!
y = -2(x^2+2x - 3) = -2(x^2+2x + 1) -1 -3) = -2(x+1)^2 +8
the vertex form of a Parabola opening up(a>0) or down(a<0),
y=a%28x-h%29%5E2+%2Bk
where(h,k) is the vertex and x = h is the Line of Symmetry
y = -2(x+1)^2 + 8