Hi I need a well explained brief explanation to each step using the substitution method. so I can learn from my mistake apparently I got this wrong

Question

1. Alonzo and Miguel scored a total of 54 points in the basketball game. Miguel scored four more points than Alonzo. Determine the number of points each person scored by writing a system of equations and solving the system by the substitution method. Make sure to identify what each variable represents.

Answer 1

m = 54/2 + 4/2 = 27+2 = 29 points

a = 54-29 = 25 points

or

m + a =54

m -a = 4

add

2m = 58

m = 29

a = 54-29 = 25