SOLUTION: How do you solve {{{3y^2-7y-5=0}}}

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Question 103202: How do you solve
3y%5E2-7y-5=0
Found 2 solutions by edjones, checkley75:
Answer by edjones(8007) About Me  (Show Source):
You can put this solution on YOUR website!
Solved by pluggable solver: SOLVE quadratic equation (work shown, graph etc)
Quadratic equation ax%5E2%2Bbx%2Bc=0 (in our case 3x%5E2%2B-7x%2B-5+=+0) has the following solutons:

x%5B12%5D+=+%28b%2B-sqrt%28+b%5E2-4ac+%29%29%2F2%5Ca

For these solutions to exist, the discriminant b%5E2-4ac should not be a negative number.

First, we need to compute the discriminant b%5E2-4ac: b%5E2-4ac=%28-7%29%5E2-4%2A3%2A-5=109.

Discriminant d=109 is greater than zero. That means that there are two solutions: +x%5B12%5D+=+%28--7%2B-sqrt%28+109+%29%29%2F2%5Ca.

x%5B1%5D+=+%28-%28-7%29%2Bsqrt%28+109+%29%29%2F2%5C3+=+2.90671775148509
x%5B2%5D+=+%28-%28-7%29-sqrt%28+109+%29%29%2F2%5C3+=+-0.573384418151758

Quadratic expression 3x%5E2%2B-7x%2B-5 can be factored:
3x%5E2%2B-7x%2B-5+=+%28x-2.90671775148509%29%2A%28x--0.573384418151758%29
Again, the answer is: 2.90671775148509, -0.573384418151758. Here's your graph:
graph%28+500%2C+500%2C+-10%2C+10%2C+-20%2C+20%2C+3%2Ax%5E2%2B-7%2Ax%2B-5+%29

Answer by checkley75(3666) About Me  (Show Source):
You can put this solution on YOUR website!
3y^2-7x-5=0
using the quadratic equation: x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+
y=(7+-sqrt[-7^2-4*3*-5])/2*3
y=(7+-sqrt[49-60])/6
y=(7+-sqrt109)/6
y=(7+-10.44)/6
y=(7+10.44)/6
y=17.44/6
y=2.907 answer.
y=(7-10.44)/6
y=-3.44/6
y=-.573 answer.