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What is the solution of the equation x2 - x - 1 + 0?...

What is the solution of the equation x2 - x - 1 + 0?

A.

x = 1.6 and x = -0.6

B.

x = -1.6 and x = 0.6

C.

x = 1.6 and x = 0.6

D.

x = -1.6 and x = -0.6

Correct answer is A

x2x1=0

Using the quadratic formula, 

x=b±b24ac2a

a = 1, b = -1, c = -1.

x=(1)±(1)24(1)(1)2(1)

x=1±1+42=1±52

x=1+2.242;x=12.242

x=3.242;x=1.242

x=1.62;x=0.61

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