Respuesta :

2x + 5x + 4 = 25
7x + 4 = 25
7x +4 (-4) = 25 (-4)
7x = 21
7x/7 = 21/7
x = 3

26 = 3b - 2 - 7b
26 = 4b - 2
26 + 2 = 4b - 2 (+2)
28/4 = 4b/4
b = 7

5m/8 - 6/8 +3m/8 = 2/8
8m/8 = 8/8
m = 1

hope this helps