Question 346098
y=0.15x
(10,1.5)(20,3)(30,4.5)
y=0.2x-4
(20,0)(30,2)(40,4)

Your intersection values of (80,12) is correct.
for each equation
take 3 values of x and calculate y
plot the two graphs
{{{graph(300,300,-1,100,-1,15,0.15x,0.2x-4)}}}
you will get 2 graphs as above

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