Question:
ABC is a triangle right-angled at B. If A(k, 1, -1), B(2k, 0, 2) and C(2 + 2k, k, 1) are the vertices of the triangle, then what is the value of k?
ABC is a triangle right-angled at B. If A(k, 1, -1), B(2k, 0, 2) and C(2 + 2k, k, 1) are the vertices of the triangle, then what is the value of k?
Options:
- a) -3
- b) -1
- c) 1
- d) 3
- a) -3
- b) -1
- c) 1
- d) 3
correct answer : d)
Explanation:
D.rs of AB = k, -1, 3
D.rs of BC = 2, k, -1
AB ^ BC
\ 2k – k – 3 = 0 Þ k = 3
D.rs of AB = k, -1, 3
D.rs of BC = 2, k, -1
AB ^ BC
\ 2k – k – 3 = 0 Þ k = 3