Question:easy

The area in the first quadrant bounded by the function \(y = (8-x)\) and the coordinate axes is ______ square units (answer in integer).

Show Hint

The line y = 8 - x meets the axes at (8,0) and (0,8), so the bounded region in the first quadrant is just a right triangle; use either integration or the (1/2) × base × height formula.
Updated On: Aug 14, 2026
Show Solution

Correct Answer: 32

Solution and Explanation

Since the three vertices of the bounded region are known exactly, the area can be found directly using the coordinate geometry shoelace formula instead of integrating.

The triangle has vertices $(x_1,y_1) = (0,0)$, $(x_2,y_2) = (8,0)$ and $(x_3,y_3) = (0,8)$, the origin and the two axis intercepts of the line $y = 8 - x$.

The shoelace (determinant) formula for the area of a triangle with these vertices is:
\[ A = \frac{1}{2}\left| x_1(y_2-y_3) + x_2(y_3-y_1) + x_3(y_1-y_2) \right| \]

Substituting the coordinates:
\[ A = \frac{1}{2}\left| 0(0-8) + 8(8-0) + 0(0-0) \right| = \frac{1}{2}\left| 0 + 64 + 0 \right| = \frac{64}{2} = 32 \]

This confirms, by a purely coordinate-geometry route with no integration at all, that the enclosed area is exactly 32 square units.
\[\boxed{A = 32 \text{ square units}}\]
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