Example 5.70 Changing Variables Consider the integral (xvvldydx. where R is the parallelogram joining the points (1. 2), R (3. 4}. (4. 3). and (6. 5} [Figure 5.?7). Make appropriate changes of variables, and write the rewiring integral. 1'1 (5'5) [3. 4} {4' 3) {1. 2) o E Figure 5.7? The region of integration for the given integral