Question

Okay I know this is going to sound like this is coming from utter laziness but I promise you it's not. I need the answers to some math problems because I promised my best friend I would hang with her today after skipping her b day for work and I need to be ready in an hour but I HAVE TO do my math first if you could help me I would totally owe you big time.

1. The quadratic equation function with roots -2 and 4 and a vertex at (1,9)
2.The quadratic equation function with roots -1 and 1 and a vertex at (0,-3)
3. The quadratic equation function with roots -1 and -7 and a vertex at (-4,-7)

Answer 1

they give you the vertex, so use the vertex form of the equation
http://www.mathwarehouse.com/geometry/parabola/standard-and-vertex-form.php
y= a(x-h)^2 + k
replace h and k the the x and y values of the vertex. example: for the first problem
the vertex is (1,9) so h=1 and k=9

now you need to find "a" use (-2,0) (the root is -2 means when x is -2 , y is zero)
plug x=-2 and y=0 into the equation and solve for "a"