SOLUTION: find the x-intercept and y-intercept of 2x^2 - 8x + 10

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Question 830937: find the x-intercept and y-intercept of 2x^2 - 8x + 10
Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!
2x%5E2+-+8x+%2B+10=y
the x-intercept is a point with coordinates (x,+0+)
so, set y=0 and solve for x
2x%5E2+-+8x+%2B+10=0
x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+
x+=+%28-%28-8%29+%2B-+sqrt%28+%28-8%29%5E2-4%2A2%2A10+%29%29%2F%282%2A2%29+

x+=+%288+%2B-+sqrt%28+64-80+%29%29%2F4+
x+=+%288+%2B-+sqrt%28+-16+%29%29%2F4+
x+=+%288+%2B-+4i%29%2F4+
solutions:
x+=+%288+%2B+4i%29%2F4+
x+=+8%2F4+%2B+4i%2F4+
x+=+2+%2B+i+

x+=+%288+-+4i%29%2F4+
x+=+8%2F4+-+4i%2F4+
x+=+2-+i+
as you can see, x+=+2+%2B+i+ and x+=+2-+i+ are complex solutions; so, there is NO x-intercept


the y-intercept is a point with coordinates (+0+,+y+)
and to find y-intercept, set x=0
2x%5E2+-+8x+%2B+10=y
2%2A0%5E2+-+8%2A0+%2B+10=y
+10=y
so, the x-intercept is at a point (0,+10+)

let's check it on a graph:
+graph%28+600%2C+600%2C+-10%2C+10%2C+-15%2C+15%2C+2x%5E2+-+8x+%2B+10%29+