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Use the quadratic formula to solve for x.42 + 6x=- 1Round your answer to the nearest hundredth.If there is more than one solution, separate them with commas.

Use the quadratic formula to solve for x.42 + 6x=- 1Round your answer to the nearest-example-1

1 Answer

4 votes

4x^2 +6x = -1

To use the quadratic formula, this needs to be in the form ax^2 +bx +c =0

4x^2 +6x +1 =0

a = 4 b = 6 and c = 1

The quadratic formula is

x = -b +- sqrt(b^2 -4ac)

-------------------------------

2a

x = -6 +- sqrt(6^2 - 4(4)(1))

-------------------------------

2(4)

x = -6 +- sqrt(36-16)

-------------------------

8

x = -6 +- sqrt(20)

--------------------

8

Taking the + solution first

x = -6+sqrt(20)

----------------- = -.190983006

8

x = -6 -sqrt(20)

------------------ = -1.309016994

8

Rounding to the nearest hundredth

-1.31, -.19

User Samuel Peter
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