Answer:
one costs 17 dollars the other costs 55 dollars
Explanation:
we have to make 2 equations using variables
x=shirt 1
y= shirt 2
y+x=72
x=3y+4
then substitute 3y+4 for x in the first equation
y+3y+4=72
subtract 4 and add y and 3y
4y=68
divide by 4
y= 17
use this for y in the second equation
x=3(17)+4
x=51+4
x=55