SOLUTION: i need help pleas use the quadriatic formula to solve each of the following quadratic equations. 2x^2 - 5x = 3

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Question 99096: i need help pleas use the quadriatic formula to solve each of the following quadratic equations.
2x^2 - 5x = 3
Found 2 solutions by aaaaaaaa, stanbon:
Answer by aaaaaaaa(138) About Me  (Show Source):
You can put this solution on YOUR website!
2x%5E2+-+5x+=+3
2x%5E2+-+5x+-+3+=+0
Solved by pluggable solver: SOLVE quadratic equation with variable
Quadratic equation ax%5E2%2Bbx%2Bc=0 (in our case 2x%5E2%2B-5x%2B-3+=+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=%28-5%29%5E2-4%2A2%2A-3=49.

Discriminant d=49 is greater than zero. That means that there are two solutions: +x%5B12%5D+=+%28--5%2B-sqrt%28+49+%29%29%2F2%5Ca.

x%5B1%5D+=+%28-%28-5%29%2Bsqrt%28+49+%29%29%2F2%5C2+=+3
x%5B2%5D+=+%28-%28-5%29-sqrt%28+49+%29%29%2F2%5C2+=+-0.5

Quadratic expression 2x%5E2%2B-5x%2B-3 can be factored:
2x%5E2%2B-5x%2B-3+=+2%28x-3%29%2A%28x--0.5%29
Again, the answer is: 3, -0.5. Here's your graph:
graph%28+500%2C+500%2C+-10%2C+10%2C+-20%2C+20%2C+2%2Ax%5E2%2B-5%2Ax%2B-3+%29

Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
2x^2 - 5x = 3
----------------------
2x^2 - 5x - 3 =0
a=2, b=-5, c=-3
x = [-b +- sqrt(b^2-4ac)]/[2a]
x = [5 +- sqrt (25-4*2*-3)]/[2*2]
x = [5 +- sqrt (49)]/4
x = [5 +- 7]/4
x = 12/4 = 3 or x= -2/4 = -1/2
===========================
Cheers,
Stan H.