Test Index
NCERT Class XI Mathematics - Straight Lines - Solutions
© examsnet.com
Question : 39 of 74
Marks:
+1,
-0
Find the points on the x-axis, whose distances from the line = 1 are 4 units.
Solution:
We have an equation of line = 1, which can be written as 4x + 3y – 12 = 0 ... (i) Let (a, 0) be the point on x-axis whose distance from line (i) is 4 units. ⇒ = 4 ⇒ = 4 ⇒ = 4 ⇒ = 4 ⇒ |4a – 12| = 20 ⇒ 4a – 12 = ± 20 ⇒ 4a = 12 ± 20 ⇒ a = 3 ± 5 i.e. a = 3 + 5 or a = 3 – 5 ⇒ a = 8 or a = – 2 Hence, the required points on the x-axis are (8, 0) and (–2, 0).
© examsnet.com
Go to Question: