Linear Equations
Recall:
New Stuff:
 Slopeintercept form of the equation.
The graph of the equation y = mx + b is a straight line with
slope m and y intercept ( 0 ; b ).
Procedure: (Writing an Equation in SlopeIntercept
Form)
To write a linear equation in slopeintercept form, solve the
equation for y .
Examples:
Write the equations in slopeintercept form. Then find the
slope and yintercept.
1. 8x + 2y = 6
2. 5x + y = 15
 Using the y intercept and the slope to draw a graph.
Procedure: (Using the y intercept and Slope to Graph
a Line)
1. Find the slope and write it as a fraction (i.e. if the
slope is 2, write it as ).
2. Find the y intercept and plot it. This is your starting
point.
3. From the starting point:
 If the slope is positive, move up the distance on the top
of the fraction and right the distance on the bottom of
the fraction to find a second point.
 If the slope is negative, move DOWN the distance on the
tope of the fraction and right the distance on the bottom
of the fraction to find a second point.
4. Starting at the second point you found above, repeat the
previous step to find a third point.
5. Connect the points with a straight line and extend the line
straight in each direction.
Example:
Graph both of the equations in the previous example on the
same set of axes.
 Solving equations graphically.
Procedure: (Solving Equations Graphically)
1. Graph each side of the equation.
2. Find all points of intersection.
3. The x coordinates of the points of intersection are the
solutions.
Example:
Solve the equation 4x  3 = 5x + 15 graphically.
