Help me, please to solve a confused emergency

Acompany is making new soccer uniforms for a team. the company uses 2.5 yards of fabric for each shirt. the company uses 82.5 yards of fabric to make shirts and shorts for 15 players. the equation and solution below represents the situation. 15(2.5+x)=82.5; x=3 what does the solution, x=3, represent?

X+ y = 5 ; x - y =3 solve using linear combination

Arectangle has a width of 5 cm and a length of 10 cm. if the width is increased by 3, how does the perimeter change?