1/5 (1/3) + 8/15= 0.6 + 8/15

Acircle has a diameter will endpoints of (-2,8) and (6, 4). what is the center of the circle

What is the value of x in the equation 2(x-4) = 4(2x + 1)?

Jack has a piece of red ribbon that is two times as long as his piece of blue ribbon. he says that he can use two different equation to find out how long his piece of red ribbon is compared to his piece of blue ribbon is. is he correct? explain his reasoning