SOLUTION: select the approximate values of x that are solutions to f(x)=0 where f(x)=-9x^2+3x+9

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Question 917539: select the approximate values of x that are solutions to f(x)=0 where f(x)=-9x^2+3x+9
Answer by MathLover1(20849) About Me  (Show Source):
You can put this solution on YOUR website!

f%28x%29=0 where f%28x%29=-9x%5E2%2B3x%2B9

0=-9x%5E2%2B3x%2B9
0=-3%283x%5E2-x-3%29 ... use quadratic formula to find x in %283x%5E2-x-3%29
x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+
x+=+%28-%28-1%29+%2B-+sqrt%28+%28-1%29%5E2-4%2A3%2A%28-3%29+%29%29%2F%282%2A3%29+
x+=+%281+%2B-+sqrt%28+1%2B36+%29%29%2F6+
x+=+%281+%2B-+sqrt%28+37+%29%29%2F6+
x+=+%281+%2B-+6.083+%29%2F6+
solutions:
x+=+%281+%2B+6.083+%29%2F6+
x+=+7.083+%2F6+
x+=+1.1805
x+=+1.18
or
x+=+%281+-+6.083+%29%2F6+
x+=+-5.083+%2F6+
x+=-0.8471666666666667
x+=+-0.85