SOLUTION: Can you help me with this? Using complete sentences, explain how to completely factor 3x2-3x-60. (3x2 the 2 is smaller and elevated) Thank you!

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Question 352561: Can you help me with this?
Using complete sentences, explain how to completely factor 3x2-3x-60.
(3x2 the 2 is smaller and elevated)
Thank you!
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
[3x%5E2+-+3x+-+60]
Make the quadratic equal to zero
[3x%5E2+-+3x+-+60+=+0]
Divide both sides by 3
[x%5E2+-+x+-+20+=+0]
Add 20 to both sides
[x%5E2+-+x+=+20]
To complete the square, take one-half of the
x term, square the result, and add this
to both sides.
[x%5E2+-+x+%2B+%28-1%2F2%29%5E2+=+20+%2B+%28-1%2F2%29%5E2]
[x%5E2+-+x+%2B+1%2F4+=+80%2F4+%2B+1%2F4]
Express each side as a square.
[%28x+-+1%2F2%29%5E2+=+%289%2F2%29%5E2]
Take the square root of both sides
[x+-+1%2F2+=+9%2F2]
Subtract 9%2F2 from both sides
[x+-+5+=+0]
and
[x+-+1%2F2+=+-9%2F2]
Add 9%2F2 to both sides
[x+%2B+4+=+0]
The factors are x+-+5
and x+%2B+4