SOLUTION: solve by using the Quadratic Formula: x^2+11x+18=0

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Question 1356: solve by using the Quadratic Formula: x^2+11x+18=0
Answer by usyim88hk(158) About Me  (Show Source):
You can put this solution on YOUR website!
First lets look at the quadratic formula:
x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+
So we get the a, b, and c from the standard form of a parabola equation
ax^2+bx+c
in this case, a=1, b=11, and c=18
Now we can use the quadratic formula:
x+=+%28%28-11+%2B-+sqrt%28+11%5E2+-+4%281%29%2818%29%29%29%2F%282%281%29%29%29
x+=+%28%28-11+%2B-+sqrt%2849%29%29%2F2%29
x+=+%28-11+%2B-7%29%2F2
x = -4/2 or -18/2
x = -2 or -9