Answer:
40
Step-by-step explanation:
34 to 40 eaasssy i think ims ry if wrong or it might be 35
 
        
             
        
        
        
<u>Answer</u>
 59°
<u>Explanation</u>
There are 2 parallel line and one transverse. 
Angles in a straight line add up to 180°
∴ 180 - (2a + 3) = 180 - 2a -3
                         = 177 - 2a
The angle (177 - 2a) corresponds to angle a in the diagram. The two corresponding angles are equal.
∴ 177 - 2a = a
   177 = a + 2a
3a  = 177 
a = 177/3
   = 59°
 
        
             
        
        
        

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9² = 12² + 15² - 2 (12) (15) cos (B)
81 = 144 + 225 - 360 cos(B)
81 = 369 - 360 cos (B)
360 cos (B) = 369 - 81
360 cos (B) = 288
cos (B) = 0.8
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Answer: Cosine B = 0.8
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12² = 15² + 9² - 2 (15)(9) cos (A)
144 = 225 + 81 - 270 Cos A
144 = 306 - 270 Cos A
270 Cos A = 162
Cos A = 3/5 or 0.6
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Answer: Cosine Angle A = 3/5
 
        
             
        
        
        
Not sure what dimensions means but this is what I got out of it , hope it helps !