SOLUTION: help me solve 3x^2-12x=63

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Question 232489: help me solve 3x^2-12x=63
Answer by jsmallt9(3758) About Me  (Show Source):
You can put this solution on YOUR website!
Because of the x%5E2 term, this is a quadratic equation. To solve quadratic equations
  1. Simplify each side
  2. Get one side equal to zero by adding or subtracting appropriate terms.
  3. Use the quadratic formula or factor
  4. If you factored in the previous step, use the Zero Product Property and solve.

Let's try this on your equation.
3x%5E2-12x=63
1. Simplify.
Your equation is already simplified.
2. Get one side equal to zero.
Subtract 63 from each side:
3x%5E2-12x-63=0
3. Factor or use the quadratic formula. (I prefer factoring when it can be done so we'll factor.)
Always start factoring with the Greatest Common Factor (GCF). Here the GCF is 3:
3%28x%5E2-4x-21%29+=+0
Always keep factoring until you can factor no more. The trinomial will factor:
3%28x-7%29%28x%2B3%29+=+0
4. Use the Zero Product Property. This property says that the only way a product can be zero is if one of the factors is zero. So our solutions will be x values that make one of the factors zero. 3 cannot be a zero. But the other two, with x in them, could be:
x-7+=+0 or +x%2B3+=+0
Solving these we get:
x+=+7 or x+=+-3