SOLUTION: Solve. 20-x^2=4

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Question 434598: Solve. 20-x^2=4
Answer by jsmallt9(3758) About Me  (Show Source):
You can put this solution on YOUR website!
20-x%5E2=4
Because of the x squared term, this is a quadratic equation. To solve a quadratic equation we want one side to be zero. Subtracing 4 from each side we get:
16-x%5E2=0
Now we factor (or use the Quadratic Formula). This factors easily as a difference of squares:
(4+x)(4-x) = 0
From the Zero Product Property we know that one of these factors must be zero. So:
4+x = 0 or 4-x = 0
Solving each of these we get:
x = -4 or x = 4
These are the solutions to your equation.