4.5 Equations of Lines

Objective A – To find the equation of a line given a point and the slope

The equation of a line can be written in the form $y = mx + b$ , when a point on the line and the slope of the line are given.
If given a point, $(x_1,y_1)$ and the slope, $m$ , then the equation can be written in Point-Slope Form: $y - y_1 = m(x - x_1)$ then rewrite into the slope-intercept form $y = mx + b$ by solving for $y$

Objective B – To find the equation of a line given two points

If given two points on the line, first find the slope between the two points. Then use the same method for a given point and slope.

Here is a worksheet to practice using the point-slope form of the equation of a line.