Question
Question: For k≠-1, the area of the triangle formed by $(x_1,y_1), (x_2,y_2), (\frac{kx_1+x_2}{k+1}, \frac{ky_...
For k≠-1, the area of the triangle formed by (x1,y1),(x2,y2),(k+1kx1+x2,k+1ky1+y2) is
A
(k+1)∣y2−y1∣
B
(k+1)∣x2−x1∣
C
∣x2−x1∣
D
0
Answer
0
Explanation
Solution
The third point is given by
(k+1kx1+x2,k+1ky1+y2)which is a weighted average of (x1,y1) and (x2,y2). This implies it lies on the line joining these two points. Hence, the three points are collinear, and the area of the triangle they form is zero.