Consider the Change of Variables X = S + 3t $\int _ { R } 2 x + 3 y d A$

Consider the change of variables x = s + 3t, y = s - 2t.
Let R be the region bounded by the lines 2x + 3y = 1, 2x + 3y = 4, x - y = -3, and x - y = 2.Find the region T in the st-plane that corresponds to region R.
Use the change of variables to evaluate $\int _ { R } 2 x + 3 y d A$ .