Answer:
23. see attached
25. no question content (see below)
26. A. Ken made a mistake between steps 1 and 2
Explanation:
23. Profit is the difference between revenue and cost. The glee club will have revenue of $2 for each cupcake sold. We can let x represent the number of cupcakes sold, so 2x will be their revenue.
The glee club has costs of $20 for booth rental. Then their profit (y) is ...
y = 2x -20 . . . . . . difference between revenue and cost
You recognize the form of this equation as being "slope-intercept" form, so you know you can graph the point (0, -20) as the y-intercept and make the line have an upward slope of 2 units rise for each 1 unit of run.
The graph is attached. (Don't forget to label the axes.)
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25. There is no question here. We observe that Aaron made a mistake in application of the distributive property when he wrote Line 3. The rest of the solution should be ...
4x -4 = 15
4x = 19
x = 19/4 = 4.75
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26. Ken made the same mistake: misapplication of the distributive property. His line 2 should have been ...
line 2: 10y -2 = 18
line 3: 10y = 20
line 4: y = 2
Ken made a mistake between steps 1 and 2.