What is the sum of 2x+1 and its opposite?

Find all the values of x that make 0.1x + 0.25(102 - x) < 17.10 true.

What is the equation of the graph below? y=sec(x)-4

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%.