Answer:
B: 6
Step-by-step explanation:
Find the mean:
5+8+4+7= 24
24/4=6
1 3 ...................rotate 3 and it is the same as 1
a
1.
2.
3.
4.
5. Step 4:
6.
Use the following properties:
So:
5.
a = 9
a^2 = 41^2 - 40^2
a^2 = 1681-1600 = 81