SOLUTION: How do I find the intercepts for: f(x) = x²-18x+79

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Question 951214: How do I find the intercepts for:
f(x) = x²-18x+79
Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!
to find the intercepts for:
f%28x%29+=+x%5E2-18x%2B79 set f%28x%29+=0 and solve for x
0=+x%5E2-18x%2B79 ...use quadratic formula
x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+ note that a=1, b=-18, and c=79
x+=+%28-%28-18%29+%2B-+sqrt%28+%28-18%29%5E2-4%2A1%2A79+%29%29%2F%282%2A1%29+
x+=+%2818+%2B-+sqrt%28+324-316+%29%29%2F2+
x+=+%2818+%2B-+sqrt%28+8+%29%29%2F2+
x+=+%2818+%2B-+sqrt%28+4%2A2+%29%29%2F2+
x+=+%2818+%2B-+2sqrt%28+2+%29%29%2F2+...simplify
x+=+%28cross%2818%299+%2B-+cross%282%29sqrt%28+2+%29%29%2Fcross%282%29+
x+=+%289+%2B-+sqrt%28+2+%29%29+
exact solutions:
x+=+9+%2B+sqrt%28+2+%29+
or
x+=+9+-+sqrt%28+2+%29+

approximate solutions:
x+=+10.41+
or
x+=+7.59+

so, intercepts are at:
(9+%2B+sqrt%28+2+%29+,0) and (9+-sqrt%28+2+%29+,0)
or
(10.41++,0) and (7.59++,0)

+graph%28+600%2C+600%2C+-5%2C+15%2C+-5%2C+15%2C+x%5E2-18x%2B79%29+