SOLUTION: How do you figure out this Factor: 5x^2 + 5x – 30

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Question 101988: How do you figure out this Factor:
5x^2 + 5x – 30
Answer by mathemanic(13) About Me  (Show Source):
You can put this solution on YOUR website!
5x^2 + 5x – 30
Suppose that two numbers: a and b satisfy conditions as such:
+a+%2A+b+=+5+%2A+-30+
+a+%2B+b+=+5+
Therefore a = 15 and b = -10.
To factorize the quadratic equation above,
+%28%285x+%2B+a%29+%2A+%285x+%2B+b%29%29+%2F+5+
+%28%285x+%2B+15%29+%2A+%285x+-+10%29%29+%2F+5+
+%285x+%2B+15%29+%2A+%28x+-+2%29+
To find the solution,
+%285x+%2B+15%29+%2A+%28x+-+2%29+=+0+
so either +%285x+%2B+15%29+=+0+ or +%28x+-+2%29+=+0+
Therefore the solutions for x is either +x%5B1%5D+=+-3+ or +x%5B2%5D+=+2+.
Cheers.