Answer:
189
Step-by-step explanation:
To find his average, we will find the mean. This means we will add 220+166+181 to get 567. When finding the mean we divide the answer but the total amount of addends. In our case we have 3 so we divide 567 by 3.
567 divided by 3 = 189
I hope this helps :DDDDDDDDDDD
points are( 6,2),(7,5) and (3,8)
X,y changes into y,-X