T = t-shirts & S = shorts

T + T + S + S = $42
T + S + S + S = $45

HOW MUCH IS A PAIR OF SHORTS?
EXPLAIN HOW YOU FOUND THE ANSWER.

A pair of shorts would cost 12 dollars.

I solved it by setting the two equations equal to one another.

2T+2S+42=T+3S+45

Minus 42, minus t, minus 2S gives:

T=S+3 So you know S is 3 more than T. Then just trial and error solve to get shorts are 12 dollars and tshirts are 9.