Test Index
NCERT Class XI Mathematics - Straight Lines - Solutions
© examsnet.com
Question : 53 of 74
Marks:
+1,
-0
Find the values of k for which the line (k – 3) x – (4 – ) y + – 7k + 6 = 0 is (a) Parallel to the x-axis, (b) Parallel to the y-axis, (c) Passing through the origin.
Solution:
Given equation of a line is (k – 3)x – (4 – ) y + – 7k + 6 = 0 ... (i) (a) The line (i) is parallel to x-axis if coefficient of x = 0 ⇒ k – 3 = 0 ⇒ k = 3 (Since Any line parallel to x-axis is of the form y = b) (b) Clearly the line (i) is parallel to y-axis if coefficient of y = 0 ⇒ (4 – ) = 0 (Since Any line parallel to y-axis is of the form x = a) ⇒ = 4, i.e. k = ± 2. (c) Since the line (i) passes through the origin if (0, 0) lies on (i) ⇒ 0 – 0 + – 7k + 6 = 0 ⇒ (k – 6) (k – 1) = 0, i.e. k = 6, 1.
© examsnet.com
Go to Question: