Leo is researching an electric bicycle. He finds this graph, which shows how much range, measured in kilometers, the bicycle gains based on charging time:
A graph plots t=charging time in minutes on the horizontal axis, from 0 to 20, in increments of 5, versus k=range gain on the vertical axis, from 0 to 70, in increments of 10, on a coordinate plane. Points are plotted as follows: (5, 20), (10, 40), and (15, 60).











A graph plots t=charging time in minutes on the horizontal axis, from 0 to 20, in increments of 5, versus k=range gain on the vertical axis, from 0 to 70, in increments of 10, on a coordinate plane. Points are plotted as follows: (5, 20), (10, 40), and (15, 60).
Leo wants an equation he can use to find how many kilometers of range the bicycle gains (

) based on how many minutes it charges (

).
Complete Leo's equation.



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