Systems of Equaions

Question

Matt is 5 years older than Lauren. In 8 years the sum of their ages will be 79. How old is Matt now?

Answer 1

M = L+5

in 8 years their ages sum to 79

M+8 + L+ 8 = 79

L+5 + L = 79-16

2L = 63-5 = 58

L = 58/2 = 29 years old for Lauren now

M = 5+29 = 34 years old for Matt now

in eight years they'll be 37 and 42 which sum to 79