Step-by-step explanation:
the total cost is, of course, first the cost to buy the copier, and then the running costs per copy made.
it is really that easy.
the equations just put this into mathematical form :
A
y = 0.02×x + 800
B
y = 0.06×x + 600
please notice, we put $600 or $800 in as constant term, because these costs are the starting costs that we have, even if we never make a single copy (x = 0).
and then the total cost goes up with every copy we make.
I cannot draw here.
so, to find the number of copies where both copier systems would cost the same, means we have to say both equating deliver the same result :
0.02×x + 800 = 0.06×x + 600
200 = 0.04×x
x = 200 / 0.04 = 5000
when making 5000 copies both costs are the same.