Question

Jan's age is 3 years less than twice Tritt's age. The sum of their ages is 30. Find their ages.

Answer 1

J - Jan's age
T - Tritt's age

(1) J + 3 = 2T
(2) J + T = 30    |subtract T from both sides
(2) J = 30 - T

subtitute (2) to (1)

30 - T + 3 = 2T
33 - T = 2T    |add T to both sides
3T = 33    |divide both sides by 3
T = 11

subtitute the value of T to (2)

J = 30 - 11
J = 19

Answer: Jan is 19 and Tritt is 11.

Answer 2

J + t = 30
j = 2t - 3

sub eq 2 into eq 1
2t - 3 + t = 30...combine like terms
3t - 3 = 30...add 3 to both sides
3t = 30 + 3
3t = 33...divide both sides by 3
t = 33/3
t = 11 <=== Tritt is 11

j = 2t - 3
j = 2(11) - 3
j = 22 - 3
j = 19 <== Jan is 19