Question

Solve the following quadratic equation.

m² + 5m + 5 = 0

Answer 1

m² + 5m + 5 = 0

Comparing the above equation with am² + bm + c = 0, we get, a = 1, b = 5, c = 5

∴ b² − 4ac = (5)² − 4 × 1 × 5 = 25 − 20 = 5

`"m" = (- b +- sqrt(b^2 - 4ac))/(2a)`

`"m" =  (- 5 +- sqrt(5))/(2(1))`

`"m" =  (- 5 +- sqrt(5))/(2)`

`"m" =  (- 5 + sqrt(5))/2       "or"         "m" = (-5 - sqrt(5))/2`

∴ The roots of the given quadratic equation are `(- 5 + sqrt(5))/2 "and" (-5 - sqrt(5))/2`.