# PSAT Math : How to find the area of an acute / obtuse triangle

## Example Questions

### Example Question #141 : Triangles

If triangle ABC has vertices (0, 0), (6, 0), and (2, 3) in the xy-plane, what is the area of ABC?

Possible Answers:

20

12

9

10

18

Correct answer:

9

Explanation:

Sketching ABC in the xy-plane, as pictured here, we see that it has base 6 and height 3. Since the formula for the area of a triangle is 1/2 * base * height, the area of ABC is 1/2 * 6 * 3 = 9.

### Example Question #61 : Triangles

The height, , of triangle  in the figure is one-fourth the length of . In terms of h, what is the area of triangle ?

Possible Answers:

Correct answer:

Explanation:

If *, then the length of  must be .

Using the formula for the area of a triangle (), with , the area of the triangle must be .