Question: Construct and evaluate definite integral(s) representing the area of the region described, using:
(a) Vertical slices
(b) Horizontal slices
1. Enclosed by y = 2x and y = 12 - x and the y-axis.
2. Enclosed by y = x2 and y = 6 - x and the x-axis.
3. Enclosed by y = 2x and x = 5 and y = 6 and the x-axis.