X+k=w-v, for x solve each equation for the indicated value

Jack did 3/5 of all problems on his weekend homework before sunday. on sunday he solved 1/3 of what was left and the last 4 problems. how many problems were assigned for the weekend?

Using elimination, what is -4x+2y=-12 4x+8y=-24

The center on a target has a diameter of 5 inches. the whole target has a diameter of 25 inches. complete the explanation for what part of the whole target is the center. the center of the target takes up % of the whole target.