Answer:
its a right angle and a its an acute angle as well so it be 5
 
        
             
        
        
        
Answer:
C
Step-by-step explanation:
Mark as brainliest plz
 
        
                    
             
        
        
        
1. Given any triangle ABC with sides BC=a, AC=b and AB=c, the following are true :
      i) the larger the angle, the larger the side in front of it, and the other way around as well. (Sine Law) Let a=20 in, then the largest angle is angle A.
       ii) Given the measures of the sides of a triangle. Then the cosines of any of the angles can be found by the following formula:
        a^{2}=b ^{2}+c ^{2}-2bc(cosA)
2. 
20^{2}=9 ^{2}+13 ^{2}-2*9*13(cosA)

400=81+169-234(cosA)   150=-234(cosA)

cosA=150/-234= -0.641
3. m(A) = Arccos(-0.641)≈130°, 
4. Remark: We calculate Arccos with a scientific calculator or computer software unless it is one of the well known values, ex Arccos(0.5)=60°, Arccos(-0.5)=120° etc 
 
        
                    
             
        
        
        
Answer:
12
Step-by-step explanation:
1. Base x Height x Length 
1 x 4 x 3= 12