Solve f^2 - 28f = 23

Evaluate

f^{2} - 28 f = 23

Move the expression to the left side

f^{2} - 28 f - 23 = 0

Substitute a= 1,b= - 28 and c= - 23 into the quadratic formula f = \frac{- b \pm b ^{2} - 4 a c}{2 a}

f = \frac{28 \pm ( - 28 ) ^{2} - 4 ( - 23 )}{2}

Simplify the expression

More Steps

f = \frac{28 \pm 876}{2}

Simplify the radical expression

More Steps

f = \frac{28 \pm 2 219}{2}

Separate the equation into 2 possible cases

f = \frac{28 + 2 219}{2} f = \frac{28 - 2 219}{2}

Simplify the expression

More Steps

f = 14 + 219 f = \frac{28 - 2 219}{2}

Simplify the expression

More Steps

f = 14 + 219 f = 14 - 219

Solution

f_{1} = 14 - 219, f_{2} = 14 + 219

Alternative Form

f_{1} \approx - 0.798649, f_{2} \approx 28.798649

Solve the quadratic equation