## Key Concepts

**Intercepts**- The
*x-*intercept is the point, \(\left(a,0\right)\), where the graph crosses the*x-*axis. The*x-*intercept occurs when y is zero. - The
*y-*intercept is the point, \(\left(0,b\right)\), where the graph crosses the*y-*axis. The*y-*intercept occurs when y is zero. - The
*x-*intercept occurs when y is zero. - The
*y-*intercept occurs when x is zero.

- The
**Find the***x*and*y*intercepts from the equation of a line- To find the
*x-*intercept of the line, let \(y=0\) and solve for*x*. - To find the
*y-*intercept of the line, let \(x=0\) and solve for*y*.**x****y**0 0

- To find the
**Graph a line using the intercepts**- Find the
*x-*and*y-*intercepts of the line.- Let \(y=0\) and solve for
*x.* - Let \(x=0\) and solve for
*y.*

- Let \(y=0\) and solve for
- Find a third solution to the equation.
- Plot the three points and then check that they line up.
- Draw the line.

- Find the
**Choose the most convenient method to graph a line**- Determine if the equation has only one variable. Then it is a vertical or horizontal line.
\(x=a\) is a vertical line passing through the

*x-*axis at*a*.\(y=b\) is a vertical line passing through the

*y-*axis at*b*. - Determine if
*y*is isolated on one side of the equation. The graph by plotting points.Choose any three values for

*x*and then solve for the corresponding*y-*values. - Determine if the equation is of the form \(Ax+By=C\), find the intercepts.
Find the

*x-*and*y-*intercepts and then a third point.

- Determine if the equation has only one variable. Then it is a vertical or horizontal line.

## Glossary

### intercepts of a line

Each of the points at which a line crosses the *x-*axis and the *y-*axis is called an intercept of the line.