Answer:
Diana has 33 and Roberto has 15.
Step-by-step explanation:
Use D for the amount of apples Diana has and R for Roberto
D=R+18
D+R=48
Use Substitution to solve the system of Equations
R+18+R=48 ----> 2R+18=48- Subtract 18
2R=30- DIvide by 2
R=15
Substitute R into another equation
D=R+18
D=15+18
D=33
