SOLUTION: I need help.. I have to solve this equation using quadratic formula 0.3y^2+0.15y-11.7=0

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Question 878202: I need help.. I have to solve this equation using quadratic formula
0.3y^2+0.15y-11.7=0
Found 2 solutions by josgarithmetic, sofiyac:
Answer by josgarithmetic(39617) About Me  (Show Source):
You can put this solution on YOUR website!
Without trying to know, the left side might be factorable, but your task is to use general solution. Just follow that formula, substitute the values from your equation. The general solution is easy to look for so your initial substitutions will be this:

y=%28-0.15%2B-+sqrt%280.15%5E2-4%280.3%29%28-11.7%29%29%29%2F%282%2A0.3%29
Simplify and compute.

Answer by sofiyac(983) About Me  (Show Source):
You can put this solution on YOUR website!
0.3y^2+0.15y-11.7=0 the quadratic formula is
x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+ plug in your values into the formula
x+=+%28-0.15+%2B-+sqrt%28+0.15%5E2-4%2A0.3%2A%28-11.7%29+%29%29%2F%282%2A0.3%29+ simplify
x+=+%28-0.15+%2B-+sqrt%28+0.0225%2B14.04+%29%29%2F%280.6%29+ simplify
x+=+%28-0.15+%2B-+sqrt%28+14.0625+%29%29%2F%280.6%29+ simplify
x+=+%28-0.15+%2B-+3.75%29%2F%280.6%29+
case 1
x+=+%28-0.15+%2B+3.75%29%2F%280.6%29+ evaluate
x+=+%283.6%29%2F%280.6%29+
x+=+6+
case 2
x+=+%28-0.15+-+3.75%29%2F%280.6%29+ evaluate
x+=+%28-3.9%29%2F%280.6%29+
x+=+6.5+