Need Help with Algebra Please - Word Problem

Question

Karen is a software saleswoman. Let y represent her total pay (in dollars). Let x represent the number of copies of Math is Fun she sells. Suppose that x and y are related by the equation y = 1800 + 70x.

1) what is the change in karen's total pay for each copy of Math is Fun she sells?

2) What is Karen's total pay if she doesn't sell any copies of Math is Fun?

Answer 1

1) $70 per the slope

2) $1800 for when x=0