In a rectangular coordinate system, what is the area of a triangle whose vertices have the coordinates (-1, 0), (7, 4), and (7, -4)?
Select the correct option
A) 29	B) 30	C) 31	D) 32	E) 33

Rationale: the triangle is symmetric about the x - axis . the part above the x - axis forms a triangle with a base of 8 and a height of 4 . the area of this part is ( 1 / 2 ) ( 8 ) ( 4 ) . we can double this to find the area of the whole triangle . the total area is ( 2 ) ( 1 / 2 ) ( 8 ) ( 4 ) = 32 . the answer is d .
Answer: D