Two numbers with a sum of 20 have a greatest common factor of 5. What are the two numbers?

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%.

Is it true or false i’m trying to pass this test so i can leave school

If f(x) = 2x + 8 and g(x) = x4, what is (gº)?