Answer:
39
Step-by-step explanation:
Let's first take the ones with numerical values into play. If you add the second and the third equations, you get 10 = 2(shoe), so the shoe is 5. Then the helmet is 4. Taking the first equation, shirt-5=4+4, so shirt = 8+5=13. Then, we have Goal post = 4+13=17. The question mark is 13+9+17=39.
