SOLUTION: I need to find the y and x intercepts of y=-2x^2-8x-5 Thank you in advance

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Question 927731: I need to find the y and x intercepts of y=-2x^2-8x-5
Thank you in advance

Answer by MathLover1(20849) About Me  (Show Source):
You can put this solution on YOUR website!
to find the y and x intercepts of y=-2x%5E2-8x-5, set x=0 to find y intercept, then set y=0 to find x intercept

y=-2x%5E2-8x-5 if x=0, we have
y=-2%2A0%5E2-8%2A0-5
y=-5
y intercept is at (0,-5)

y=-2x%5E2-8x-5 if y=0, we have
0=-2x%5E2-8x-5...use quadratic formula
x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+

x+=+%288+%2B-+sqrt%28+64-40+%29%29%2F-4%29+
x+=+%288+%2B-+sqrt%28+24+%29%29%2F-4%29+
x+=+%288+%2B-+4.89%29%2F-4%29+
solutions:
x+=+%288+%2B+4.89%29%2F-4%29+
x+=+12.89%2F-4+
x+=-3.2+
or
x+=+%288+-4.89%29%2F-4%29+
x+=+3.11%2F-4+
x+=-0.8+



x intercept is at (-3.2+,0) and (-0.8+,0)


+graph%28+600%2C+600%2C+-5%2C+5%2C+-10%2C+5%2C+-2x%5E2-8x-5%29+