On the xy-coordinate plane, point A lies on the y-axis and point B lies on the x-axis. Points A, B, and C form a right triangle with a 90-degree angle at point C and the triangle has an area of 20. If AC is parallel to the x-axis, and BC is parallel to the y-axis, which of the following could be the coordinates of point C?  Answers: A) (3, 7) B) (-8, 4) C) (5, -8) D) (-2, 10) E) (-5, -5)
The area of the triangle formed will be:   1/2 * base * height =   1/2 * |(X-coordinate of point (5, -8))| * |(Y-coordinate of point (5, -8))| = 20   Thus |product of coordinates of point (5, -8)| = 40   The answer is (5, -8).
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On the xy-coordinate plane, point A lies on the y-axis and point B lies on the x-axis. Points A, B, and C form a right triangle with a 90-degree angle at point C and the triangle has an area of 20. If AC is parallel to the x-axis, and BC is parallel to the y-axis, which of the following could be the coordinates of point C?