What is the missing number?

the missing number is 6

Step-by-step explanation:

let x represent the missing number

15 - 7 = x +2

8 = x + 2

-2      -2

6 = x

x = 6

im not quite sure if this is right but i got 5.6 oisutuve

step-by-step explanation:

fist on the left goes with the third on the right. second on the left goes with the fourth on the right. third on the left goes with the second on the right. the fourth on the left goes with first on the right