Answer:

Step-by-step explanation:
All the angles in a triangle add up to 
Every right angle triangle has a right angle in it which is 
So to find the remaining angle, you do
-
-
= 
I don’t understand the equation but you can use Photomath to solve any equation you need to solve. It’s and app for free.
Fraction would be 30/100 and decinal would be .30 and ratio would be 30/100