Question

Why is the answer (A)?

Answer 1

`(1)/(2)x^2+mx-5=0 \\ \\ x= \frac{-mб \sqrt{m^2-4* (1)/(2)*(-5) } }{2* (1)/(2) }= (-mб √(m^2+10) )/(1)=-mб √(m^2+10)`