Answer:
Each shirt cost $7 Â and each pair of shorts cost $17 .
Step-by-step explanation:
let shirts be represented as x
let shorts be represented as y
Younger brother spent $79 on 4 new shirts and 3 pairs of shorts.
4 x + 3 y = $79 Â Â .......equation 1
Older brother purchased 7 new shirts and 8 pairs of shorts and paid a total of $185.
7 x + 8 y = $185 Â .......equation 2
multiply equation 1 by 7 and equation 2 by -4 and add both equations to get the value of y.
7 × (4 x + 3 y = $79)   ⇒       +28 x + 21 y = $553
-4 × (7 x + 8 y = $185)  ⇒       -28 x - 32 y = - $740
                             0  - 11 y  = - $187   ⇒  -11 y  = - $187
y = [tex]\frac{- $187}{- 11}[/tex]  ⇒  y = $17
shorts = y = $17
put value of y in equation 1
4 x + 3 ( $17 ) = $79  ⇒   4x + $51 = $79  ⇒  4x = $79 - $51
4x = $28  ⇒  x = [tex]\frac{$28}{4}[/tex]  ⇒  x = $7
Shirts = x = $7