module 4 topic 3 notes
TRANSCRIPT
Module 4 Topic 3
Writing Linear Equations
The equation for slope-intercept form is
m is the slopeslope measures the steepness of the linem=-4/2=-2
b is the y-interceptb is where the line crosses the y-axis.
bmxy
-4
2
Write the equation of the line that has a slope of -4 and y-intercept of 5.
bmxy
54 xy
We use Point-Slope form, when we are given: a point and a slope!
Write the equation of the line that passes
through (-3,5) and has a slope of 2.
What are we given? We are given the
slope is 2!
AND…we are given a point
(-3,5).
Final Answer
Write the equation of the line that passes through
(-3,5) and (-1,9) .
What are we given? We are given 2
points, but no slope!
Can we find the slope? Do
we have enough info?
Yes, we can use…
22
4
)3(1
59
m
Write the equation of the line that passes through
(-3,5) and (-1,9) .
Now that we know that the slope is 2, we can use either point to find the
equation of the line.
Summary1.When given the slope and y-intercept: y=mx+b.2.When given 1 point and the slope, do point slope: y – y1=m(x-x1).3.When given 2 points, and no slope, one must find the slope (m=y2-y1 over x2-x1), then use either point for the point slope form.
Now proceed to Mastery Assignments!