Y = sit ups, x= days
y= 2x + 15
33 = 2x + 15 (subtract 15 from both sides)
18 = 2x (divide both sides by 2)
9 = x, 9 days
To figure this out you can do 7.2/8.2, because you are trying to figure out how much of the total was used, and percentages would not be more than 100%. Doing this you would get ~.878. To convert this to a percent, you would just multiply it by 100, which would give you 87.8%. The question states to round to the nearest whole percent, leaving you with 88%. This means that 88% of the revenue was spent.
Hope that helped, don't be shy to comment on this if you have any questions about my explanation :)
The point-slope form:
m - slope
The formula of a slope:
We have the points (-2, 3) and (1, -3). Substitute:
The standard form: Ax + By = C. Convert:
<em>use distributive property</em>
<em>subtract 3 from both sides</em>
<em>add 2x to both sides</em>
-1/5x - 18 = 2
-x - 18(5) = 2(5)
-x = 10 + 90
-x = 100
x = -100
