How to find the constant variation for each direct variation

Solve |x| > -9 a) {x|x< -9 or x> 9} b) all reals c) no solution

Y=21.95x+10 y=22.45x solve by substitution

The population of a bacteria colony grows by a consistent percentage each hour and can be modeled by the function y = 500(1.16)t. what does the value 500 represent in the function?