Question

On a coordinate plane, triangle R S T has points (negative 3, 2), (3, 2), and (negative 1, 1). An altitude is drawn from point T to point U at (negative 1, 2).
What is the area of triangle RST?

6 square units
9 square units
12 square units
18 square units

Answer 1

Compute the base RS: distance between (-3,2) and (3,2) is 6. The altitude TU from T(-1,1) to U(-1,2) has length 1. Area = 1/2 * base * height = 1/2 * 6 * 1 = 3 square units.

So the correct area is 3 square units — none of the given choices (6, 9, 12, 18) is correct.