SOLUTION: please help with this one. Use the quadratic formula to solve the equation: 16x^2 - 40x +5 = 0 thank you in advance

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Question 43459This question is from textbook college algebra
: please help with this one.
Use the quadratic formula to solve the equation:
16x^2 - 40x +5 = 0
thank you in advance This question is from textbook college algebra

Answer by aaaaaaaa(138) About Me  (Show Source):
You can put this solution on YOUR website!
Solved by pluggable solver: SOLVE quadratic equation with variable
Quadratic equation ax%5E2%2Bbx%2Bc=0 (in our case 16x%5E2%2B-40x%2B5+=+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=%28-40%29%5E2-4%2A16%2A5=1280.

Discriminant d=1280 is greater than zero. That means that there are two solutions: +x%5B12%5D+=+%28--40%2B-sqrt%28+1280+%29%29%2F2%5Ca.

x%5B1%5D+=+%28-%28-40%29%2Bsqrt%28+1280+%29%29%2F2%5C16+=+2.36803398874989
x%5B2%5D+=+%28-%28-40%29-sqrt%28+1280+%29%29%2F2%5C16+=+0.131966011250105

Quadratic expression 16x%5E2%2B-40x%2B5 can be factored:
16x%5E2%2B-40x%2B5+=+16%28x-2.36803398874989%29%2A%28x-0.131966011250105%29
Again, the answer is: 2.36803398874989, 0.131966011250105. Here's your graph:
graph%28+500%2C+500%2C+-10%2C+10%2C+-20%2C+20%2C+16%2Ax%5E2%2B-40%2Ax%2B5+%29