What is the equation of the circle?

Asystem of equations has 1 solution.if 4x-y=5 is one of the equations , which could be the other equation ?

You can ride your bike around your block 6 times and the whole neighborhood 5 times in 16 minutes. you can ride your bike around your block 3 times and the whole neighborhood 10 times in 23 minutes. how long does it take you to ride around the neighborhood?

Will mark brainlist what is the slope of the line passing through the points (-2, -8) and (-3,-9)? -7/5-5/71-1