Which of the following are the solutions of the equation 2x^2+2x=4-x

(A) x=4 and x=1
(B) x=4 and x= -1/2
(C) x= 3+√35/4 and x=3-√35/4
(D) x=-3+√41/4 and -3-√41/4
(E) -3+i√23/2 and -3-i√23/2



Answer :

2x² + 2x = 4 - x
      +   x       + x
2x² + 3x = 4
2x² + 3x - 4 = 0
x = -(3) +/- √((3)² - 4(2)(-4))
                     2(2)
x = -3 +/- √(9 + 32)
                 4
x = -3 +/- √(41)
              4
x = -3 +/- 6.4
            4
x = -0.75 + 1.6
x = -0.75 + 1.6      x = -0.75 - 1.6
x = 0.85                x = -16.75

The answer is equal to D. x = -0.75 + √(41)/4 and x = -0.75 - √(41)/4.

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