SOLUTION: Can someone help me solve the system: {y=3x+9 {y=x^2-2x-5. thanks so much!

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Question 113579: Can someone help me solve the system:
{y=3x+9
{y=x^2-2x-5.
thanks so much!
Answer by MathLover1(20849) About Me  (Show Source):
You can put this solution on YOUR website!

Can someone help me solve the system:
y=3x%2B9…………..(1)
y=x%5E2-2x-5.………(2)

y=x%5E2-2x-5.………substitute y from (1) in (2)
3x%2B9+=+x%5E2-2x-5
0+=+x%5E2-2x+%96+3x+-5+-+9
+x%5E2+-+2x+%96+3x+-5+%96+9+=+0
+x%5E2+%96+5x++%96+14+=+0….use square root formula

x%5B1%2C2%5D=%28-b+%2B-+sqrt+%28b%5E2+-4%2Aa%2Ac+%29%29+%2F+%282%2Aa%29

x%5B1%2C2%5D=%285+%2B-+sqrt+%2825+%2B+56+%29%29+%2F+2
x%5B1%2C2%5D=%285+%2B-+sqrt+%2881+%29%29+%2F+2
x%5B1%2C2%5D=%285+%2B-+9+%29+%2F+2

x%5B1%5D=%285+%2B+9+%29+%2F+2

x%5B1%5D=+14+%2F+2
x%5B1%5D=+7
x%5B2%5D=%285+-+9+%29+%2F+2
x%5B2%5D=+-+4++%2F+2
x%5B2%5D=+-+2