Question

Solve 5x^2-2x-1=0 with the quadratic formula

Answer 1

a = 5 b = -2 c = -1

x = [--2 +-sq root(-2 ^ 2 - 4 * 5 * -1)] / 2 * 5

x = [2 +-sq root (4 - -20)] / 10

x = [2 + sq root (24)] / 10

x = (2 + 4.8989794856 ) / 10

x = 6.8989794856 / 10

x1 = .6899

x2= (2 - 4.8989794856 ) / 10

x2 = - 2.8989794856 / 10

x2 = -.2899

Explanation: