Graph the two equations, and look for points where they intersect
## Substitution
Solve for a variable in the equation, then substitute it into another equation.
EG, given the below systems:
$$ y = x+3 $$
$$ x = 3y + 2 $$
You can substitute values, like this:
$$ x = 3(x+3) + 2 $$
Then once you have $x$, you can plug it back into the first equation to solve for y.
## Elimination
To solve a system of equations by elimination, you add the two equations together and see if something cancels out.
A simple example might look like this:
$$ 2x + 3y = 23 $$
$$ 4x -3y = -13 $$
You "add" the two equations together, getting:
$$ 6x + 0y = 10 $$
You now know that $6x = 10$.
If you don't have two values that evenly cancel out, like $3$ and $4$, you can find the least common multiple and multiply the entire equation so that those two are equal. In this case, you'd multiply one equation by 4, and one equation by 3.
