The fractions 1/10 and 1/5 convert to 0.1 and 0.2 respectively.
So the equations y = (1/10)x+60 and y = (1/5)x are the same as y = 0.1x+60 and y = 0.2x in that order.
We see that the nonmember cost graph is steeper since the slope 0.2 is larger than 0.1; the further we move away from 0, the steeper the slope. A steeper slope means that you pay more per token. This is the unit cost.
Specifically, you would pay 0.20-0.10 = 0.10 more dollars per token if you are a nonmember compared to if you are a member.
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Also, notice that the y intercepts of y = 0.1x+60 and y = 0.2x are 60 and 0 in that order. The members pay an up front fee of $60 before they can buy any tokens. Nonmembers don't have to pay an upfront cost.
Visually, the graph for the members will be much higher up compared to the nonmembers graph. Both lines are increasing, but the members graph is increasing less overall. At some point, the two lines intersect. After this point, it makes more sense to be a member.