SOLUTION: how do you find the x-intercepts of the graph y=x^2-2x-3 ?

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Question 699020: how do you find the x-intercepts of the graph y=x^2-2x-3 ?
Answer by MathLover1(20849) About Me  (Show Source):
You can put this solution on YOUR website!

to find the x-intercepts of the graph y=x%5E2-2x-3, set y=0 and solve for x using quadratic formula

0=x%5E2-2x-3

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

x+=+%28-%28-2%29+%2B-+sqrt%28+%28-2%29%5E2-4%2A1%2A%28-3%29+%29%29%2F%282%2A1%29+

x+=+%282+%2B-+sqrt%28+4%2B12+%29%29%2F2+

x+=+%282+%2B-+sqrt%28+16+%29%29%2F2+

x+=+%282+%2B-+4%29%2F2+
solutions:
x+=+%282+%2B+4%29%2F2+
x+=6%2F2+
x+=3+
and
x+=+%282+-+4%29%2F2+
x+=-2%2F2+
x+=-1+

so, the x-intercepts are the points: (3,0) and (-1,0)

+graph%28+600%2C+600%2C+-10%2C+10%2C+-10%2C+10%2C+x%5E2-2x-3%29+