Equations often model real-world situations. When an equation with two variables models a real-world situation, one variable is independent and the other is dependent.
Let's look at an example. Each sandwich at Sam's Subs costs
$
5
.
The equation
c
=
5
s
tells you the total cost,
c
,
for
s
sandwiches.
The total cost depends on the number of sandwiches. So,
c
is the dependent
variable,
and
s
is the independent
variable.
Let's look at another example. Marie can read 30 pages in one hour. The equation
p
=
30
h
tells you the total number of pages,
p
,
Marie can read if she reads for
h
hours.
The number of pages Marie reads depends on the number of hours she spends reading. So,
