Solve the following system of equations for the value of x and y
y=3x+9 y=5x

Aflute is on sale for 20% off. including the discount and 8% tax, the sales price is $216.

Aremote-controlled boat can travel at 4 feet per second in calm water. the boat traveled 48 feet with the current, and then it traveled 16 feet against the current in the same amount of time. how fast is the current?

What is the slope of any line parallel to the line 8x+9y=3 in the standard (x,y) coordinate plane?