we are given that 
angle(ACF)=90
angle(ACB)=61
sum of all angles along any line is 180
so, we get 
angle(ACF)+angle(ACD)=180
we can plug value 
90+angle(ACD)=180
angle(ACD)=90
now, we can use formula 
angle(ACD)=angle(ACB)+angle(BCD)
now, we can plug values
and we get 
90=61+angle(BCD)
90-61=61-61+angle(BCD)
angle(BCD)=29................Answer
 
        
                    
             
        
        
        
Answer:
157 books in each row
Step-by-step explanation:
24 rows=3768 books
1 row=3768/24 books
 =157 books
Therefore,Each row contains 157 books
Mark this answer as brainliest....
 
        
             
        
        
        
Answer:
5/6
Step-by-step explanation:
The total number of writing utensils is 6, explaining the denominator. the numbers of pens added together is 5, explaining the numerator. 
 
        
             
        
        
        
The perimeter of a shape is the sum of the lengths of its sides.
So, to find the perimeter of this quadrilateral, all we have to do is add the side lengths and simplify.
(x² - 6) + (2x + 5) + (x² - 3x) + (4x² + 2x)
x² + x² + 4x² + (-3x) + 2x + 2x + (-6) + 5
6x² + (-3x) + 2x + 2x + (-6) + 5
6x² + x + (-6) + 5
6x² + x + (-1)
6x² + x - 1
So, the perimeter of the quadrilateral is the quantity (6x² + x - 1).
Hope this helps!
 
        
             
        
        
        
Answer:
it would be a triangle
Step-by-step explanation:
Do good!