Writing Linear Equations – Part 2
Objective: The students will be able to use slope-intercept form to write the equation of a line given the
slope and a point, and 2 points.
Now for the fun stuff! 
We are going to graph equations using a point and slope!
If we are given a point (x, y) and a slope (m), we almost have everything we need to write our
equation in the form y = mx + b. What is the only thing we don’t have? __________________
To find our y-intercept, we just plug in what we have and solve the equation
for b!
Examples: Write the slope-intercept form of the following lines.
1. passes through (4, -2) slope = ½
x : ______
m: ______
y : ______
b : ______
y = mx + b
Equation of line: ____________________
2. m = 3, passes through (-1, 4)
3. slope: -3/4, point: (0, 3)
4. m = -2, passes through (-2, -1)
5. m = 3/2, passes through (4, 6)
6. m = 0, passes through (1, 1)
7. slope = -2/5, point: (-4, 5)
Recall: How do we find the slope of a line given two points?
b.
m=
So if all we are given is two points, can we find the equation of a line??
1. Find the slope using the formula above.
2. Now you have your slope (m) and a point! Look familiar?!?!
Examples:
8. (0, 3) and (2, 4)
1) Find the slope:
2) Now pick one of your points! Your problem is exactly what we were just doing 
9. (-3, 1) and (1, 5)
10. (2, -4) and (0, 6)
11. (-2, 0) and (-2, 3)
12. (-4, 7) and (2, -1)
13. (4, 1) and (-5, 1)
14. (5, 2) and (0, -3)