Answer:
 ΔABC and  ΔXYZ are SIMILAR by SSS property of similarity.
Step-by-step explanation:
SSS Similarity Theorem:
Two triangles are said to be similar if their  CORRESPONDING SIDES are proportional.
In ΔABC and  ΔXYZ, if  , then  △ABC∼△YZX
  , then  △ABC∼△YZX
Here, in ΔABC and  ΔXYZ
AB = 9, BC = x , AC = 12 
Similarly, XY = 3, YZ = 2, ZX = 4
Here, 

⇒ Corresponding sides are in the ratio of 3, if BC  =6 units
Hence, if BC  = 6 units, then the ΔABC and  ΔXYZ are SIMILAR by SSS property of similarity.
 
        
             
        
        
        
Answer:
138 cm.
Step-by-step explanation:
So first, we find the S.A. of the front and back.
The diagram says the side length of the front is 3 cm. and 3 cm.
3x3=9. So then, the back is also 9 cm, 9+9=18.
Now to find the S.A.'s of the four sides, you have to see the side lengths of each of them. The side lengths are 3 and 10.
3x10=30. This means each of them is 30 cm.
30x4=120. 120 is the total surface area of the four sides.
To find the total surface area of the whole rectangle, you add all the surface areas.
120+18=138 cm. (Not squared, since it's surface area and not area.)
 
        
             
        
        
        
Angle is x. sup - adds up to 180. comp adds up to 90
180-x = 3(90-x)+40
180-x = 270-3x+40
180-x = 310-3x
180+2x = 310
2x = 130
x=65
        
             
        
        
        
Dividing thirty-two by five we get
x=32/5
 =6•4