SOLUTION: I need help with this: 3x^2+9x-30=0 Thanks

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Question 1036503: I need help with this: 3x^2+9x-30=0 Thanks
Found 2 solutions by josmiceli, MathTherapy:
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
+3x%5E2+%2B+9x+-+30+=+0+
You can complete the square to find roots
Divide both sides by +3+
+x%5E2+%2B+3x+-+10+=+0+
+x%5E2+%2B+3x+=+10+
Take 1/2 of the coefficient of the +x+ term,
square it and add to both sides
+x%5E2+%2B+3x+%2B+%283%2F2%29%5E2+=+10+%2B+%283%2F2%29%5E2+
+x%5E2+%2B+3x+%2B+9%2F4++=+10+%2B+9%2F4+
+x%5E2+%2B+3x+%2B+9%2F4++=+49%2F4+
+%28+x+%2B+3%2F2+%29%5E2+=+%28+7%2F2+%29%5E2+
Take the square root of both sides
++x+%2B+3%2F2+=+7%2F2+
+x+=+4%2F2+
+x+=+2+
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and, taking the negative square root of +49%2F4+
+x+%2B+3%2F2+=+-7%2F2+
+x+=+-10%2F2+
+x+=+-5+
The roots are +x+=+2+ and +x+=+-5+
---------------
Here's the plot of the given equation:
+graph%28+400%2C+600%2C+-7%2C+4%2C+-38%2C+5%2C+3x%5E2+%2B+9x+-+30++%29+

Answer by MathTherapy(10552) About Me  (Show Source):
You can put this solution on YOUR website!

I need help with this: 3x^2+9x-30=0 Thanks
3x%5E2+%2B+9x+-+30+=+0

3%28x%5E2+%2B+3x+-+10%29+=+3%280%29 ------- Factoring out GCF, 3

x%5E2+%2B+3x+-+10+=+0

(x + 5)(x - 2) = 0

x + 5 = 0        OR      x - 2 = 0

highlight_green%28matrix%281%2C3%2C+x+=+-+5%2C+or%2C+x+=+2%29%29