C. 5
Step-by-step explanation:
The coeff of

Is 15.
So by that we can write 3m = 15
m is 5.
Distribute
10+4x+4+5
Combine like terms
19+4x
Final answer: 4x+19
50% or 1/2 of 4 is 2 50% or 1/2 of 6 is 3 so then just add them to the respective number since its going up by 50% or 2 in by 3 in \[\frac{ 6 }{ 9}\]