4x+3y=21, where x is time and y is velocity in kilometers per hour. use this function to determine when a certain particle will reach 30km/hr.

The diameter of a circular chip is doubled to use in a new board game. the area of the new chip will be

Name the most appropriate metric unit for each measurement

Two cyclists 84 miles apart start riding toward each other at the same. one cycles 2 times as fast as the other. if they meet 4 hours later, what is the speed (in mi/h) of the faster cyclist?