Answer:
s=7
p=3s
Step-by-step explanation:
The perimeter is the side length times 3
So the equation would be p=3s
Plug in 21 for p
21=3s
That means s=7
lete try to help you my insta it's Cruzz_ and other letters
Your total balance is 154.
You start with 120.
+30
-21
+45
Hope that helps.
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