SOLUTION: Hey, I have a math test tomorrow and I honestly don't understand anything about Quadratic Equations. Could you explain how to do the following question to get me started? 2x(squ

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Question 872879: Hey, I have a math test tomorrow and I honestly don't understand anything about Quadratic Equations. Could you explain how to do the following question to get me started?
2x(squared) + 3x + 1 = 0
Found 2 solutions by Alan3354, psbhowmick:
Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
2x^2 + 3x + 1 = 0
Can be factored:
(2x + 1)*(x + 1) = 0
2x+1 = 0
x = -1/2
------------
x + 1 = 0
x = -1
===================
This always works:
Solved by pluggable solver: SOLVE quadratic equation (work shown, graph etc)
Quadratic equation ax%5E2%2Bbx%2Bc=0 (in our case 2x%5E2%2B3x%2B1+=+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=%283%29%5E2-4%2A2%2A1=1.

Discriminant d=1 is greater than zero. That means that there are two solutions: +x%5B12%5D+=+%28-3%2B-sqrt%28+1+%29%29%2F2%5Ca.

x%5B1%5D+=+%28-%283%29%2Bsqrt%28+1+%29%29%2F2%5C2+=+-0.5
x%5B2%5D+=+%28-%283%29-sqrt%28+1+%29%29%2F2%5C2+=+-1

Quadratic expression 2x%5E2%2B3x%2B1 can be factored:
2x%5E2%2B3x%2B1+=+%28x--0.5%29%2A%28x--1%29
Again, the answer is: -0.5, -1. Here's your graph:
graph%28+500%2C+500%2C+-10%2C+10%2C+-20%2C+20%2C+2%2Ax%5E2%2B3%2Ax%2B1+%29

Answer by psbhowmick(878) About Me  (Show Source):
You can put this solution on YOUR website!
2x%5E2+%2B+3x+%2B+1+=+0
2x%5E2+%2B+2x+%2B+x+%2B+1+=+0
2x%28x+%2B+1%29+%2B+1%28x+%2B+1%29+=+0
%282x+%2B+1%29%28x+%2B+1%29+=+0
Either x+=+-1%2F2 or x+=+-1

If you need any further help on this, feel free to contact me.