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PolarNik [594]
3 years ago
15

4x^2-2x-4=0 solve using quadratic formula

Mathematics
1 answer:
MArishka [77]3 years ago
4 0

Answer:

Step-by-step explanation:

Although you can start with 4x^2-2x-4=0, it's just slightly easier to reduce the coefficients.  4x^2-2x-4=0 becomes 2x^2 - x - 2 = 0.

The discriminant (part of the quadratic formula) is b^2 - 4ac.  Using b = -1. a = 1 and c = -2, we get (-1)^2 - 4(2)(-2), or 17.

                                                       -b ± √(b^2 - 4ac)

Then the quadratic formula   x = ---------------------------

                                                                 2a

                                         -(-1) ± √17           1 ± √17

takes on the values  x = -----------------  =  ---------------

                                                  4                      4

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