Boy im a about to roast you 
        
             
        
        
        
Since the angle  
100
°  is in the second quadrant, the reference angle formula is  A
r
=
180
°
−
A
c.   A
r
=
180
°
−
100
°
The reference angle is  A
r
=
80
°
.
80
°
 
        
             
        
        
        
Use PEMDAS to figure out the order of operations:
Parentheses
Exponents
Multiplication/
Division
Addition/
Subtraction
Solve (-4 + -6) first, as this is in parentheses:


Solve 5.3 * -10 next, as this is multiplication:


Now we can solve the equation:

The answer is 63.
 
        
        
        
Answer: m∠ M′N′O′ = 90 degrees
Step-by-step explanation: Hope that helps ! I am not sure if  I am right but I think I am ! 
 
        
                    
             
        
        
        
Answer:
Step-by-step explanation:
- x² - 16 = 0
- x² = 16
- x = √16
- x = ± 4