Question

How do you know if an ordered pair (5,11) is a solution to y=2x+1?

Answer 1

If you are given a solution to an equation, knowing whether it is a solution is usually a simple matter of substituting it into the equation and checking that both sides match.

Explanation:

Substituting `x=color(red)(5)`, `y=color(blue)(11)` in

`y=2x+1`

gives

`color(blue)(11) = 2times color(red)(5)+1`

This is valid (since both sides equal the same number - 11), and so `(5,11)` is a solution to `y=2x+1`