Move the variables to one side and the constants to the other
50q - 43 = 52q - 81
50q (-52q) - 43 (+43) = 52q (-52q) - 81 (+43)
50q - 52q = -81 + 43
-2q = -38
isolate the q, divide -2 from both sides
-2q/-2 = -38/-2
q = -38/-2
q = 19
hope this helps
If this is math where is the number or is it just word problem