Solve x^2 - 9x - 12 = 0

Evaluate

x^{2} - 9 x - 12 = 0

Substitute a= 1,b= - 9 and c= - 12 into the quadratic formula x = \frac{- b \pm b ^{2} - 4 a c}{2 a}

x = \frac{9 \pm ( - 9 ) ^{2} - 4 ( - 12 )}{2}

Simplify the expression

More Steps

x = \frac{9 \pm 129}{2}

Separate the equation into 2 possible cases

x = \frac{9 + 129}{2} x = \frac{9 - 129}{2}

Solution

x_{1} = \frac{9 - 129}{2}, x_{2} = \frac{9 + 129}{2}

Alternative Form

x_{1} \approx - 1.178908, x_{2} \approx 10.178908

Solve the quadratic equation