SOLUTION: I got this reply back for my question....I can't find an answer unless I am doing something wrong. Thanks for checking into it for me! Question 240789: Hello, I need some help

Algebra ->  Quadratic Equations and Parabolas -> SOLUTION: I got this reply back for my question....I can't find an answer unless I am doing something wrong. Thanks for checking into it for me! Question 240789: Hello, I need some help       Log On


   

Question 240880: I got this reply back for my question....I can't find an answer unless I am doing something wrong. Thanks for checking into it for me!
Question 240789: Hello,
I need some help to:
1. Solve the following equation using quadratic formula
2x^2-3x-1=0
The solution set is? ________
Thanks!!
Answer by vleith(1971) About Me (Show Source):
Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
1. Solve the following equation using quadratic formula
2x^2-3x-1=0
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Solved by pluggable solver: SOLVE quadratic equation (work shown, graph etc)
Quadratic equation ax%5E2%2Bbx%2Bc=0 (in our case 2x%5E2%2B-3x%2B-1+=+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=%28-3%29%5E2-4%2A2%2A-1=17.

Discriminant d=17 is greater than zero. That means that there are two solutions: +x%5B12%5D+=+%28--3%2B-sqrt%28+17+%29%29%2F2%5Ca.

x%5B1%5D+=+%28-%28-3%29%2Bsqrt%28+17+%29%29%2F2%5C2+=+1.78077640640442
x%5B2%5D+=+%28-%28-3%29-sqrt%28+17+%29%29%2F2%5C2+=+-0.280776406404415

Quadratic expression 2x%5E2%2B-3x%2B-1 can be factored:
2x%5E2%2B-3x%2B-1+=+%28x-1.78077640640442%29%2A%28x--0.280776406404415%29
Again, the answer is: 1.78077640640442, -0.280776406404415. Here's your graph:
graph%28+500%2C+500%2C+-10%2C+10%2C+-20%2C+20%2C+2%2Ax%5E2%2B-3%2Ax%2B-1+%29


= (3/4) ħsqrt(17)/4