Answer:
+or- sqrt(3/4)
Explanation:
If x + m is a factor, that means that when x = -m the equation equals 0. Sub -m into x
0 = (-m)^2 - 5m(-m) + 3
0 = m^2 - 5m^2 + 3
0 = -4m^2 + 3
Factorise
0 = -4(m^2 - 3/4)
0 = -4(m + sqrt(3/4))(m - sqrt(3/4))
:. m = +or- sqrt(3/4)