SOLUTION: find the x and y intercepts f(x)=x^2-8x+2

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Question 153941: find the x and y intercepts f(x)=x^2-8x+2

Answer by orca(409) About Me  (Show Source):
You can put this solution on YOUR website!
The function is y=x%5E2-8x%2B2
To find the y-intercept, let x =0, so y+=0%5E2-8%2A0%2B2=2
Thus the y-intercept is 2.
To find the x-intercept, let y=0, and determine the corresponding values of x by solving the following quadratic equation.
x%5E2-8x%2B2=0
Substitute
a = 1
b=-8
c=2
into the quadratic formula below
x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+
So
x+=+%28-%28-8%29+%2B-+sqrt%28+%28-8%29%5E2-4%2A1%2A2+%29%29%2F%282%2A1%29+
x+=+%288+%2B-+sqrt%28+64-8+%29%29%2F%282%29+
x+=+%288+%2B-+sqrt%28+56+%29%29%2F%282%29+
x+=+%288+%2B-+sqrt%28+14%2A4+%29%29%2F%282%29+
x+=+%288+%2B-+2sqrt%28+14+%29%29%2F%282%29+
x+=+4+%2B-+sqrt%28+14+%29
So the x-intercepts are 4%2Bsqrt%2814%29 and 4-sqrt%2814%29
graph%28300%2C300%2C-10%2C10%2C-10%2C10%2Cx%5E2-8x%2B2%29