First, we plug in all the numbers under the columns "Kitchen Sink", "Bathroom Sink" and "Shower" in our matrix calculator as A. Then, we plug in all the numbers under "Total Selling Price" in our matrix calc as B. Then, we perform the equation A^-1 * B. We will look to the 3rd row for this, since shower is our "z" and the third row represents z
Since profit is determined by .15 * 120, we calculate this. Your answer is 18.
