U would simpiphy it to then get the awnser
We first obtain the equation of the lines bounding R.
For the line with points (0, 0) and (8, 1), the equation is given by:

For the line with points (0, 0) and (1, 8), the equation is given by:

For the line with points (8, 1) and (1, 8), the equation is given by:

The Jacobian determinant is given by

The integrand x - 3y is transformed as 8u + v - 3(u + 8v) = 8u + v - 3u - 24v = 5u - 23v
Therefore, the integration is given by:
13 - 4/7 = <span>12.4285714286 Or when you round it 12.43</span>
What is the question can't help with ought it