m=michaels's age now
b=brandon's age now
m-18=michael's age 18 years ago
b-18=brandon's age 1 yeas ago
m is 3 times b
m=3b
18 years ago
m-18=9(b-18)
so
sub 3b for m
3b-18=9(b-18)
distribute
3b-18=9b-162
minus 3b both sides
-18=6b-162
add 162 bot sides
144=6b
divde both sides by 6
24=b
sub back
m=3b
m=3(24)
m=72
brandon is 24 and michale is 72
