HELP!! Find another way to express the scale 1 m = 4 cm

Acircle has a radius of 5/6 units and is centered at (3.6, 7.8) write the equation of this circle

How many solutions does the nonlinear system of equations graphed below have?

Tom can paint the fence in 12 hours, but if he works together with a friend they can finish the job in 8 hours. how long would it take for his friend to paint this fence alone?