Respuesta :

To get the answer for this question is to: 

Divide 56 by 72 = 0.777777778 because 0.777777778 * 72 = 56 cm. 

Since 72 cm is related to the side length of 9 cm, take 0.777777778 and multiply it by 9 and you will get 7 for the missing side length. 

To get the value of X for the equation to equal 7, take the 7 you got for the missing side length and add it to 20 to get 27 (20 + 7 = 27). Then, take the 27 and divide it by the 3, and you will get 9 for X. 

Example: 
7 + 20 = 27 
27 / 3 = X 
9 = 9

&

3x - 20 
= 3(9) - 20 
= 27 - 20 
= 7 

The correct answer for the value of X is: 9 

Hope this helps! 

~ ShadowXReaper069

Answer:

9cm

Step-by-step explanation:

i took the test