need help answering this question

Question

Malik is 3 years older than Leah. In 5 years the sum of their ages will be 43. How old is Malik now?

Answer 1

let X = Leah's age     then X + 3 = Malik's age

 

in 5 years, Leah's age will be X + 5, and Malik's age will be X + 3 + 5 or X + 8

 

thus, (X + 5) + (X + 8) = 43     So, 2X + 13 = 43   X = (43 - 13)/2 = 15

 

so, Leah is 15 and Malik is 18; in 5 years, Leah will be 20 and Malik will be 23; the sum of their ages will be 43