Can someone help me with this with the work please I don’t know how to do this

Answer:
9. 45.36
10. 24.44
Step-by-step explanation:
9. Find the height, 10^2 - 8.4^2, take the square root of it
Then take the total base legnth and plug it into the equation A=(H x B)/2
10. 7^2 - 5.2^2, take the square root then take the total base legnth and plug it into the equation A=(H x B)/2