Check the picture below.
now, since we know what "f" is, let us use the CNT triangle with the small COR one.

Answer:
35%
Step-by-step explanation:
Use photomath it tells you everything.
Answer:
x=8
Step-by-step explanation:
start by setting angle a equal to angle b
next add 21 to the opposite side
then subtract 2x from the opposite side
finally you're left with x=8
Answer:
-30x^2 sqr2x
Step-by-step explanation: