SOLUTION: What is the Quadratic Formula Answer to this: If the quadratic formula is used to solve 2x(x + 5) = 4, what are the solutions? and Solve this quadratic equation using

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Question 256419: What is the Quadratic Formula Answer to this:
If the quadratic formula is used to solve 2x(x + 5) = 4, what are the solutions?

and

Solve this quadratic equation using the quadratic formula.
x^2 + 8x - 5 = 0
Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
What is the Quadratic Formula Answer to this:
If the quadratic formula is used to solve 2x(x + 5) = 4, what are the solutions?
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The solutions are the same, regardless of what method is used. There is no "Quadratic Formula Answer", only an answer, or solution(s).
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2x(x + 5) = 4
x(x + 5) - 2 = 0
x%5E2+%2B+5x+-+2+=+0
Solved by pluggable solver: SOLVE quadratic equation (work shown, graph etc)
Quadratic equation ax%5E2%2Bbx%2Bc=0 (in our case 1x%5E2%2B5x%2B-2+=+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=%285%29%5E2-4%2A1%2A-2=33.

Discriminant d=33 is greater than zero. That means that there are two solutions: +x%5B12%5D+=+%28-5%2B-sqrt%28+33+%29%29%2F2%5Ca.

x%5B1%5D+=+%28-%285%29%2Bsqrt%28+33+%29%29%2F2%5C1+=+0.372281323269014
x%5B2%5D+=+%28-%285%29-sqrt%28+33+%29%29%2F2%5C1+=+-5.37228132326901

Quadratic expression 1x%5E2%2B5x%2B-2 can be factored:
1x%5E2%2B5x%2B-2+=+%28x-0.372281323269014%29%2A%28x--5.37228132326901%29
Again, the answer is: 0.372281323269014, -5.37228132326901. Here's your graph:
graph%28+500%2C+500%2C+-10%2C+10%2C+-20%2C+20%2C+1%2Ax%5E2%2B5%2Ax%2B-2+%29

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and
Solve this quadratic equation using the quadratic formula.
x^2 + 8x - 5 = 0
Solved by pluggable solver: SOLVE quadratic equation (work shown, graph etc)
Quadratic equation ax%5E2%2Bbx%2Bc=0 (in our case 1x%5E2%2B8x%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=%288%29%5E2-4%2A1%2A-5=84.

Discriminant d=84 is greater than zero. That means that there are two solutions: +x%5B12%5D+=+%28-8%2B-sqrt%28+84+%29%29%2F2%5Ca.

x%5B1%5D+=+%28-%288%29%2Bsqrt%28+84+%29%29%2F2%5C1+=+0.58257569495584
x%5B2%5D+=+%28-%288%29-sqrt%28+84+%29%29%2F2%5C1+=+-8.58257569495584

Quadratic expression 1x%5E2%2B8x%2B-5 can be factored:
1x%5E2%2B8x%2B-5+=+%28x-0.58257569495584%29%2A%28x--8.58257569495584%29
Again, the answer is: 0.58257569495584, -8.58257569495584. Here's your graph:
graph%28+500%2C+500%2C+-10%2C+10%2C+-20%2C+20%2C+1%2Ax%5E2%2B8%2Ax%2B-5+%29