Respuesta :

10m² + 100m + 250 = 0
10m² + 50m + 50m + 250 = 0
m(10m + 40) 5(10m +50) = 0
(m+5)(10m+40) = 0
m= -5 or  -4

Hope this helps!
ZoeBelle
I believe this is the correct answer:
10(m+5)^2