Answer:
The answer to your question is Kevin is 6 years old.
Step-by-step explanation:
Process
1.- Assign a letter to Daniel and another letter to Kevin
Daniel = d
Kevin = k
2.- Write equation that help to solve this problem
k = d + 3 equation l
k = 4d equation ll four years ago
3.- Solve the system by substitution. Substitute equation ll in equation l
4d = d + 3
-Solve for d
4d - d = 3
3d = 3
d = 1
-Find k
k = 1 + 3
k = 4
4.- Calculate the age Kevin has now
Kevin's age = 4 + 2
= 6
