How do i do y=-5 5x+4y=-20? ? i need

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?

Solve the following inequalities and show the solution on a number line. 2x+3< 3(4x+5)

Awater truck is filling a swimming pool. the equation that represents this relationship is y=19.75x where y is the number of gallons of water in the pool and x is the number of minutes the truck has been filling the pool.