Solve x^2 -1= -2x

Evaluate

x^{2} - 1 = - 2 x

Move the expression to the left side

x^{2} - 1 + 2 x = 0

Rewrite in standard form

x^{2} + 2 x - 1 = 0

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

x = \frac{- 2 \pm 2 ^{2} - 4 ( - 1 )}{2}

Simplify the expression

More Steps

x = \frac{- 2 \pm 8}{2}

Simplify the radical expression

More Steps

x = \frac{- 2 \pm 2 2}{2}

Separate the equation into 2 possible cases

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

Simplify the expression

More Steps

x = - 1 + 2 x = \frac{- 2 - 2 2}{2}

Simplify the expression

More Steps

x = - 1 + 2 x = - 1 - 2

Solution

x_{1} = - 1 - 2, x_{2} = - 1 + 2

Alternative Form

x_{1} \approx - 2.414214, x_{2} \approx 0.414214

Solve the quadratic equation