Question

Solve this quadratic equation using the quadratic formula. x^2 + 8x - 5 = 0

Answer 1

x = -b (+-) sq rt ((b^2 - 4(a)(c))/2a)
a = 1, b = 8, c = -5

x = (-8 (+-) sq rt (8^2 - 4(1)(-5) / 2(1))
x = (-8 (+-) sq rt (64 +20)/2)
x = (-8 (+-) (sqrt 84)/2)
x = -4 + sqrt 21 and x = -4 - sqrt 21