I think #1 is wrong but i can't figure it out

Answer:
Step-by-step explanation:
x=6
y=4
5x-y^2 :2
5×6 - 4 ^2 :2
30 - 16 :2
30 - 8
22 (the wright answer)
Circle the mistake :x =6 and y =4 it's not x=4 and y=6
Explain the mistake :when you calculed with x=4 and y=6 the final answer is wrong.