If y varies directly as x and x= 15 when y = 5, find x when y= 9

Liz is shipping a package to her friend.the maximum weight of a medium flat-rate box is 20 pounds,including the box which weighs 6 ounces.write and solve an inequality to describe the possible weight ,w, of the contents that liz will ship to her friend if she must use a medium flat-rate box.

Equation for the calculation double 2 and then add 5

Graph the function =gx+2x3 and give its domain and range using interval notation.