If charlie decides to ride her bike and goes 18 km west at a velocity of 0.13 km/s west, how long would it take her to reach her destination?

If cos(2x) = tan^2(y), show that cos(2y) = tan^2(x).

Elena is paid a constant rate for each hour she works. the table shows the amounts of money that elena earned for various amounts of time that she worked.

Starting at home, emily traveled uphill to the hardware store for 606060 minutes at just 666 mph. she then traveled back home along the same path downhill at a speed of 121212 mph. what is her average speed for the entire trip from home to the hardware store and back?