standard_description: Use similar triangles to explain why the slope m is the same between any two distinct points on a non-vertical line in the coordinate plane; derive the equation y = mx for a line through the origin and the equation y = mx + b for a line intercepting the vertical axis at b.
problem_activity: Task
Kell  works at an after-school program at an elementary school. The table below shows how much money he earned every day last week.
{"table": [{"thead": [{"tr": [{"td": [{}, {"_value": "Monday"}, {"_value": "Wednesday"}, {"_value": "Friday"}]}]}], "tbody": [{"tr": [{"td": [{"_value": "Time worked"}, {"_value": "1.5 hours"}, {"_value": "2.5 hours"}, {"_value": "4 hours"}]}, {"td": [{"_value": "Money earned"}, {"_value": "\\$12.60"}, {"_value": "\\$21.00"}, {"_value": "\\$33.60"}]}]}]}]}
Mariko has a job mowing lawns that pays \$7 per hour.
Who would make more money for working 10 hours? Explain or show work.
Draw a graph that represents $y$, the amount of money Kell would make for working $x$ hours, assuming he made the same hourly rate he was making last week.
Using the same coordinate axes, draw a graph that represents $y$, the amount of money Mariko would make for working $x$ hours.
How can you see who makes more per hour just by looking at the graphs? Explain.


aligns: no