First we find the y-intercept of this graph whic in this case is -3. Then we plot two pints on the graph and caculate the rise over run which is 2/1=2. Finally, we get the equation- y=2x-3.
Sales tax is .30 cents because 2.39+1.59=3.98 multiply by the sales tax which would be .075 after you move the decimal. you get .2985 cents so round it up to .30 cents
