Question

Coach Johnson is 10 years older than Tim. When Tim started football 3 years ago, Coach Johnson was twice his age. How old is Tim now?

Answer 1

Write equation with variables J and T.

J is 10 years older than T
=> J = T + 10

J was twice T's age 3 years ago
=> J-3 = 2(T-3)
=> J = 2(T-3)+3

Substitute in original equation and find T.

Answer 2

Huh

Answer 3

What part of it is confusing?

Answer 4

What do you mean by substitute in original equation?

Answer 5

J = T + 10
J = 2(T-3)+3
=> 2(T-3)+3 = T + 10
=> .........
You can now find T.

Answer 6

Tim is now 13 year old. and Coach is 23 year. 3 year ago : Tim was 10 year old and Coach was 20 year old.

Method of GT is correct.