Question

Lisa is a software saleswoman. Her monthly salary is

$2200

plus an additional

$120

for every copy of Math is Fun she sells.

Let

S

represent her total salary this month (in dollars), and let

N

represent the number of copies of Math is Fun she sells. Write an equation relating

S

to

N

, and then graph your equation using the axes below.

Answer 1

Solution

If S is the total salary (in $) and N is the number of copies, then an equation relating S to N is

Total salary

S = 2200 + 120N

Rewriting the equation becomes,

S = 120N + 2200

which is analogous to the equation of the straight line

y = mx + C

The plot of S vs N will be a straight line with a slope of 120 and a y-intercept of $ 2200

.

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