Question 16 (OR 1 st question)

The points A(1, –2) , B(2, 3), C (k, 2) and D(–4, –3) are the vertices of a parallelogram. Find the value of k.    Subscribe to our Youtube Channel - https://you.tube/teachoo

1. Class 10
2. Solutions of Sample Papers for Class 10 Boards
3. CBSE Class 10 Sample Paper for 2019 Boards

Transcript

Question 16 (OR 1st question) The points A(1, –2) , B(2, 3), C (k, 2) and D(–4, –3) are the vertices of a parallelogram. Find the value of k. Let’s first draw the figure We know that Diagonals of parallelogram bisect each other So, O is mid-point of AC & O is mid-point of BD 1 mark Finding mid−point of AC We have to find x coordinate of O x−coordinate of O = (𝑥1 + 𝑥2)/2 Where x1 = 1 , x2 = k Putting values x−coordinate of O = (1 + 𝑘)/2 = (𝑘 + 1)/2 1/2 mark Finding mid−point of BD We have to find x coordinate of O x−coordinate of O = (𝑥1 + 𝑥2)/2 Where x1 = 2 , x2 = –4, Putting values for x−coordinate x−coordinate of O = (2 + (−4))/2 = (−2)/2 = –1 …(2) 1/2 mark Comparing (1) & (2) (𝑘 + 1)/2 = –1 k + 1 = –1 × 2 k + 1 = –2 k = –2 – 1 k = – (2 + 1) k = –3 Hence, k = –3 1 mark

CBSE Class 10 Sample Paper for 2019 Boards

Class 10
Solutions of Sample Papers for Class 10 Boards 