Question

Use the image to answer the question.

An illustration shows a 10 by 10 grid. A non-right triangle is enclosed within the grid. The first vertex is at the top of row 2 and the right of column 4. The second vertex is at the top of row 9 and the right of column 4. The third vertex is at the top of row 6 and the right of column 9.

Find the area of the non-right triangle. The base and height are found by counting the squares.

(1 point)

32.5 square units

65 square units

17.5 square units

35 square units

Answer 1

The vertices are at (4,2), (4,9) and (9,6). The base between the first two points is 7 units (rows 2 to 9) and the height (horizontal distance to x=9) is 5 units. Area = 1/2·7·5 = 17.5 square units.