SOLUTION: y=-3x^2+4 find the roots.Please show me the steps.

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Question 594113: y=-3x^2+4 find the roots.Please show me the steps.
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
y=-3x%5E2%2B4

0=-3x%5E2%2B4

-3x%5E2%2B4=0

3x%5E2-4=0


Now use the quadratic formula to solve


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

x+=+%28-%280%29%2B-sqrt%28%280%29%5E2-4%283%29%28-4%29%29%29%2F%282%283%29%29

x+=+%280%2B-sqrt%280-%28-48%29%29%29%2F%286%29

x+=+%28%22%22%2B-sqrt%2848%29%29%2F6

x+=+%28sqrt%2848%29%29%2F6 or x+=+%28-sqrt%2848%29%29%2F6

x+=+%284%2Asqrt%283%29%29%2F6 or x+=+%28-4%2Asqrt%283%29%29%2F6

x+=+%282%2Asqrt%283%29%29%2F3 or x+=+%28-2%2Asqrt%283%29%29%2F3


So the exact roots are x+=+%282%2Asqrt%283%29%29%2F3 or x+=+%28-2%2Asqrt%283%29%29%2F3

These roots approximate to x+=+1.1547 or x+=+-1.1547