Question : What is the area of the triangle PQR given P(4,0) Q(0,3) R(7,4)?
A. 12.5
B. 14
C. 10√2
D. 16
E. 25
Answer: [spoiler]A[/spoiler]
Though this sounds simple, I aint able to solve it...
![Embarassed :oops:](./images/smilies/embarassed.png)
Mathsbuddy wrote:You could:
1)Draw a sketch of PQR on x-y axes.
2)Now draw a rectangle to surround it, vertices: (0,0), (0,4), (7,0), (7,4)
3) Work out the area of the rectangle R = 7 * 4 = 28
4) Work out the areas of the 3 triangles inside the rectangle that surround triangle PQR:
Triangle 1: Area = 1 * 7/2 = 3.5
Triangle 2: Area = 4 * 3/2 = 6
Triangle 3: Area = 3 * 4/2 = 6
Sum of 3 triangle areas, S = 15.5
5) Subtract R - S = 28 - 15.5 = 12.5
Answer (A) 12.5
Does this help?
Question : What is the area of the triangle PQR given P(4,0) Q(0,3) R(7,4)?
A. 12.5
B. 14
C. 10√2
D. 16
E. 25