2*4 =8 +18*4=72...............................................................................
If you are trying to find the y intercept then you have already found it, it is 4. From that point you would then draw the rest of the slope.
Instead of drawing from (0,0) you would go up 4 units and then do rise over run (7/3) to plot your line.
35h x $11ph = 385, 385 x 52 = 20,020
20,020 = 15,600 = 4,420.
She earns ~$20,000 per year, but spends $4,420 per year.