This could mean...
1) Do what your heart desires, if your heart wants to do something, do it.
This should be figurive language but not for sure what you lookin for. Hope that helps

1) x=9, because we can use the Pythagorean theorem, x^2 + 144 = 225, x^2 = 81
2)
, because 6^2 +6^2 = 72, 
3)
, because 
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18.D
19.A
20.C
21.B
theses are going to be your answers
Answer:
The main property of wood that determines it's strength or weakness would be its density.
Explanation: