06-01-2006, 09:03 AM
I am trying to solve: 2x^2 + 5x = 11x + 20
I need help!
06-01-2006, 09:40 AM
2x^2 + 5x = 11x + 20
Since the x^2 terms tells us that this is a quadratic equation, the first step in solving quadratics is to gather all terms to one side of the equation:
2x^2 + 5x - 11x - 20 = 0
2x^2 - 6x - 20 = 0
Since all coefficients are even numbers, you can divide both sides by 2 to simplify things a bit:
x^2 - 3x - 10 = 0
(x - 5)(x + 2) = 0
The only way for two factors to multiply together and get 0 is that one of the factors must be 0. So:
x - 5 = 0, OR, x + 2 = 0
Solving these, we get:
x = 5, OR, x = -2
You should now check these answers in the original equation to see if they make true statements.
Hope that helps...
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