Question

which of the following is a solution to the quadratic equation -x^2 + x = -10? assume that the solution has been rounded to the nearest hundredth if applicable.
x = 1.7
x = 0.27
x = 0.77
x = 3.7

Answer 1

Solve -x^2 + x = -10 → x^2 - x - 10 = 0.
x = [1 ± sqrt(1 + 40)]/2 = [1 ± sqrt(41)]/2.

sqrt(41) ≈ 6.4031, so the positive root is (1 + 6.4031)/2 ≈ 3.7016 ≈ 3.7.
Thus x = 3.7.