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I need help with this question can you explain it step by step so I can know how to do the math

I need help with this question can you explain it step by step so I can know how to-example-1
User Enjoylife
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Answer:

Explanation:


7x^2 - 4x - 4 = 0

The quadratic formula is x = (-b±
√(b^2 - 4ac))/2a when
ax^2+bx+c=0.

Use direct substitution.

x = (-(-4)±
√((-4)^2-4(7)(-4)))/2(7)

simplify

x = (4±
√(16+112))/14

x = (4±
√(128))/14

factor greatest perfect square out of
√(128)

x = (4±
√(64)*√(2))/14

simplify

x = (4±
8*√(2))/14

greatest common factor

x = (2(2)±
4(2)*√(2))/7(2)

x = (2)(2±
4*√(2))/7(2)

x = (2±
4*√(2))/7

Possible solutions for quadratic equation


x_(1) =
(2+4*√(2))/(7)


x_(2) =
(2-4*√(2))/(7)

User Diegomontoyas
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