The equation of a line is defined by: y=mx+b
Step 1: Find the slope (rise over run) so, the rise is 15.7 and the run is 6. 15.7/6=2.62
y=2.62x+b
Step 2: Find the b value (y intercept) - this is where the line goes through the y axis. In this case, it's 15.7
Step 3: add the slope and the b value together - y=2.62x+15.7
Well if you are looking for the profit margin we need how much is was when she bought it, because it doesn't say, you can't say It's a increase or a decrease, so you could say this is a investment.
But considering you put this under mathematics I assume there is more to this question you forgot to post.
Same question
x+y=30
x is 1/5 of y
x=y/5
subsitute
y/5+y=30
multily both sidse by 5
y+5y=150
add
6y=150
divide both sides by 6
y=25
subsitute
x=y/5
x=25/5
x=5
the numbers are 5 and 25