Answer: 
16.7 Units
Step-by-step explanation:
To find the length of r, you set up the equation as sin(45)= 4.9/r. Then you get r by itself changing it to r = 4.9/sin(45). Then you can find that r = 6.9. Since this is an isosceles triangle, n^1 has to be equal to 4.9. Then you add all the side lengths together. 4.9 + 4.9 + 6.9 = 16.7 units
 
        
                    
             
        
        
        
Answer:
XZ = 2.5 BD
Step-by-step explanation:
Comparing the two triangles,
 =
 = 
 =
 = 
⇒ XZ = 
          = 15
XZ = 15
So that,
BD:XZ = 6:15
            = 1:2.5
Therefore, the relationship between BD and XZ is XZ = 2.5 BD. 
 
        
             
        
        
        
Answer:
The line AB, with A(Ax, Ay), B(Bx, By) and midpoint M(Mx, My) satisfying:
Ax + Bx = 2Mx
Ay + By = 2My
=>
2 + Bx = 2*1
5 + By = 2*2
=> Bx = 0
=> By = -1
=> B(0, -1)
Hope this helps!
:)