The money he receives from his parents would be the equation 15 + 4.55h, since he is guaranteed to recieve $15 (hence why there is no variable to possibly change that term) and receives $4.55 per extra hour of chores.
The money he receives from Mrs. Smith is 7.85h, since he earns $7.85 for each hour of work which he completes.
The sum of these amounts would be 15 + 4.55h + 7.85h.
If you add like terms you get the equation 15 + 12.40h.
