In a rectangular coordinate system, what is the area of a triangle whose vertices have the coordinates (3, 0), (6, 3), and (6, -3)? Choose the correct option:
A) 9	B) 10	C) 11	D) 12	E) 13
The triangle is symmetric about the x-axis.   The part above the x-axis forms a triangle with a base of 3 and a height of 3.   The area of this part is (1/2)(3)(3).   We can double this to find the area of the whole triangle.   The total area is (2)(1/2)(3)(3) = 9.   The answer is 9.
<result>A</result>
In a rectangular coordinate system, what is the area of a triangle whose vertices have the coordinates (3, 0), (6, 3), and (6, -3)?