42 because x is equal to its corresponding side
Make a change of coordinates:


The Jacobian for this transformation is

and has a determinant of

Note that we need to use the Jacobian in the other direction; that is, we've computed

but we need the Jacobian determinant for the reverse transformation (from

to

. To do this, notice that

we need to take the reciprocal of the Jacobian above.
The integral then changes to

Answer:
m = 
Step-by-step explanation:

Good evening
Answer:
<h2>384</h2>
Step-by-step explanation:
s = 8 ⇒ 6s^2 = 6(8)²
= 6×64
= 384
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:)