How do I do substitution equations

out of the equations in the system, pick the one that has the least amount of funky numbers. then make that equation equal to either x or y(or any other variable dependin on what kind of systems youre doing, usually just x and y in algebra 1). Then plug that equation into the other one and solve.

example:

x+3y=41

2x+2y=15

then change first equation

x=41-3y

plug it in

2(41-3y) +2y=15

simplify and solve

82-6y+2y=15

82-4y=15

82-15=4y

67=4y

67/4=y

then substitute the y value back into one of the equations and you have your answer for x.

P.S. algebra is really annoying...I'm in 9th grade Algebra2/trig....not that hard but really annoying...