Explanation:
x² + 11x + 121/4 = 125/4
x² + 11x + 121/4 - 125/4 = 0
x² + 11x - 1 = 0
after that apply quadratic formula
x = ( -b + or - √b² - 4ac ) ÷ 2a
x = (-11 + or - √11² - 4×1×-1 ) ÷ 2×1
+ = 0.090169....
- = -11.090168.....
x = 0.090 or x = -11.09