The document provides examples of solving direct variation problems by setting up proportions and cross-multiplying. It gives three example problems: 1) writing the direct variation equation for a line through (0,0) and (4,2), 2) finding the value of k in an equation, and 3) finding an x value when given a y value. It also provides links to additional direct variation example resources.

1. Module 5, Topic 1 Examples
Some Help from Mrs. M

2. Direct Variation
 Is an equation of the form y = kx, where k is the
slope of the line
 Is proportional…so we can set up our problems
as a proportion and then cross-multiply to solve
Here’s an example to go back over how to cross-
multiply:
Solve:

3. Some Direct Variation Examples
1. Write the direct
variation equation of 2. Find the value of k in
the line through (0,0) the direct variation
and (4, 2). equation 4y = 5x.
 Solve for y:
 k=

4. 3. x varies directly as y. When x = 4,
y = 12. Find x when y = 36.
 Direct variation means proportional change, so
let’s write a proportion and substitute our given
information:

5. Some Other Examples
 http://quiz.uprm.edu/tutorials/direct_var/direct_var
_right.xml
 http://www.freemathhelp.com/direct-variation.html