While sitting in the quad on central campus, I counted 9 students riding 2-wheeled mopeds or 3-wheeled scooters, which made a total of 21 wheels. How many mopeds and how many scooters passed by me?

Translate the word phrase into a math expression. 15 fewer than the product of 4 and a number. (pls immediately)

The manufacturer of a new product developed the following expression to predict the monthly profit, in thousands of dollars, from sales of the productwhen it is sold at a unit price of x dollars.-0.5x^2 + 22x - 224what is represented by the zero(s) of the expression? a.the profit when the unit price is equal to 0b.the unit price(s) when the profit is equal to 0c.the profit when the unit price is greatestd.the unit price(s) when profit is greatest

Select the two pairs of figures that are similar.