Answer:
Step-by-step explanation:
We are gonna call ''K'' the constant of proportionality:
So,
as a fraction : 81/100
C
Use the pythagorean theorem
a² + b² = c²
3² + 4² = c²
9 + 16 = c²
25 = c²
5 = c
18 = 2·9 = 2·3²
answer: 2·3²
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