1. A used book store also started selling used CDs and videos. In the first week, the store sold a combination of 40 CDs and videos. They charged $4 per CD and S6 per video and the total sales were $180. Determine the total number of CDs and videos sold.
he total number of CDs and videos sold.

Lindsay is creating a bridge out of dried pasta and glue. in her plans, she sketches the graph to determine the lengths of the noodles, in centimeters, needed for the arch to increase the length of the bridge in 1 centimeter increments. which function did lindsay use to create her design? f(x) = (x – 5)2 + 8 f(x) = –(x + 5)2 + 8 f(x) = 0.5(x + 5)2 + 8 f(x) = –0.5(x – 5)2 + 8

The position of a moving particle is given by the position function: f(t)=-9t-t^2-0.2t^3+0.1t^4 a. at what time does the particle reverse direction? b. when is the displacement positive? (round one decimal place and answer in interval notation) c. when is the displacement negative? (round one decimal place and answer in interval notation) d. when is the particle’s acceleration positive? (round one decimal place and answer in interval notation) e. when is the particle’s acceleration negative? (round one decimal place and answer in interval notation)

How do you determine if an ordered pair is a solution to a given equation?