# How do you determine whether (-1, -1) and (1, -1) is a solution to y < 2x + 1?

Jul 23, 2015

$\left(1 , - 1\right)$ is a solution to the inequality $y < 2 x + 1$.

#### Explanation:

$y < 2 x + 1$

Substitute $\left(- 1 , - 1\right)$ and $\left(1 , - 1\right)$ for $x$ and $y$ into the inequality.

Point $\left(- 1 , - 1\right)$
$x = - 1$
$y = - 1$

$- 1 < 2 \left(- 1\right) + 1$ =

$- 1 < - 2 - 1$ =

$- 1 < - 3$

This is a false statement. $\left(- 1 , - 1\right)$ is not a solution.

Point $\left(1 , - 1\right)$
$x = 1$
$y = - 1$

$- 1 < 2 \left(1\right) + 1$ =

$- 1 < 2 + 1$ =

$- 1 < 3$

This is a true statement. $\left(1 , - 1\right)$ is a solution.