Try this option:
1. the sides of the biggest triangle are 16; x and √(16²-x²); the sides of the smallest triange are x;5 and y. The smallest triangle ~ the biggest triangle. Using the property of the similar triangles:

2. according to the Pyphagorean theorem (in the smallest triangle):

answer: y=√55.
Check the picture below.
now, since we know what "f" is, let us use the CNT triangle with the small COR one.

Answer:
2187
Step-by-step explanation: 27 times 81 equals 2187
Answer:
1030
Step-by-step explanation:
30+1000=1030
Answer:
Hi
Step-by-step explanation: