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14. Solve -4x2 - 7x = -5.

User Shea Levy
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1 Answer

1 vote

Answer:

x=−7/8±129/8

Explanation:

Assuming that is a -4x^2, i'll solve it. So, -4x^2 - 7x = -5. This is a quadratic, so move all the numbers to one side (and variables). So, -4x^2 - 7x + 5 = 0. Divide everything by -1, to make the coefficient of the x squared positive. This leaves: 4x^2 + 7x -5 = 0. Now, factoring attempts: (2x-1)(2x+5). This does not work, sadly, so we must find other methods. Using the quadratic formula would be easier than factoring, so use the quadratic formula. This gives us the answers of -7 plus or minus sqrt(129) all over 8. The quadratic formula comes in handy!

User Hafiz
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