The difference between three times x and four. how do u solve that and put it into a equation

Adepartment store purchases screen-printed t-shirts at a cost of $5 per shirt. they mark up the price 150% (making the selling price 250% of the store's purchase price) and put them on the sales floor. every month that a t-shirt doesn't sell, the store reduces the selling price by 25%.

What term makes it inconsistent y=2x - 4

Reflect the point (7,0) across the y-axis