Answer:
(c, b)
Step-by-step explanation:
Add the coordinates together and divide by 2
x coordinates: 2c + 0 = 2c, divided by 2 = c
y coordinates: 0 + 2b = 2b, divided by 2 = b
2.5 /10 = 10 / x
100 = 2.5x
40 =x
Just calculate second term - first term = -4 - (-15)