What is the solution of the equation 2x-y=9

Cody worked 42.5 hours per week in july. this is 12.25 hours more per week than he worked in june.how many hours did cody work per week in june?

Graph the system: f(x)= 3/x-2; f(x)= 1/2x + 2

Write a function for a rotation 90 degrees counter clockwise about the origin, point 0