SOLUTION: I am pushing in as a teacher aide the problem is the school has jumped me by about 2 yrs in my math...I just don't remember...Here is the problem -2x^2+8x+20=0

Question 214675: I am pushing in as a teacher aide the problem is the school has jumped me by about 2 yrs in my math...I just don't remember...Here is the problem
-2x^2+8x+20=0
Answer by nerdybill(7384) (Show Source): You can put this solution on YOUR website!
Starting with:
-2x^2+8x+20=0
Multiply both sides by -1:
2x^2-8x-20=0
Divide both sides by 2:
x^2-4x-10=0
Always try to factor to find the answer first. In this case, it can't be factored so you must resort to the quadratic equation. Doing so yields:
x = {5.7412, -1.742}
.
Details of quadratic:

Solved by pluggable solver: SOLVE quadratic equation with variable

Quadratic equation (in our case ) has the following solutons:

For these solutions to exist, the discriminant should not be a negative number.

First, we need to compute the discriminant : .

Discriminant d=56 is greater than zero. That means that there are two solutions: .

Quadratic expression can be factored:

Again, the answer is: 5.74165738677394, -1.74165738677394. Here's your graph: