28 degrees. This is because the first angle is 12 degrees, the third is x degrees and the second is 5x. You know that in a triangle the angles add up to 180 degrees so 12 + 5x + x = 180. Then you get 6x =168 and x =28 degrees. (**x being the thrid angle**)
        
             
        
        
        
Answer:
Θ = 157.7°
Step-by-step explanation:
Given
cosΘ = - 0.925
Since cosΘ < 0 then Θ is in the second or third quadrant.
Since 0° ≤ Θ ≤ 180° then Θ is in the second quadrant. thus
Θ =  (- 0.925) = 157.7° ← angle in second quadrant
(- 0.925) = 157.7° ← angle in second quadrant
 
        
                    
             
        
        
        
You know a1. 
So find a2, a3, and so on until a7. 
a(1) = 12
a(2) = 16
a(3) = 20
a(4) = 24
a(5) = 28
a(6) = 32
a(7) = 36
Each is 4 more than the previous.
        
             
        
        
        
Download the app photo math and there is the answer