Sagot :
Answer:
3 po ang sagot
Step-by-step explanation:
pa brainlist plss
Answer:
Formula for getting a perimeter of square is S+S+S+S or 4S
Given:21xy - 8
4(21xy-8)
84xy -24 , simplify
7xy - 2
Hence, The perimeter of a square whose side measure 21xy -8 is 7xy-2.