# Ex 10.1, 4 - Chapter 10 Class 11 Straight Lines

Last updated at May 29, 2018 by Teachoo

Last updated at May 29, 2018 by Teachoo

Transcript

Ex10.1, 4 Find a point on the x-axis, which is equidistant from the points (7, 6) and (3, 4). Let the given points be A(7, 6) & B (3, 4) Let C be a point on the x-axis Coordinates of C = C(x, 0) Given that point C is equidistant from the points A & B Hence, Distance AC = Distance BC We know that distance between two points (x1 , y1)&(x2 , y2)is D = (( 2 1)2 + ( 2 1)2) Distance between A(7, 6) & C(x, 0) AC = (( 7)^2 + (0 6)2) = (( 7)^2 + 36) Distance between B(3, 4) & C(4, 0) BC = (( 3)^2 + (0 4)2) = (( 3)^2 + 16) Since, AC = BC (( 7)^2 + 36) = (( 3)^2 + 16) Squaring both sides ( (( 7)^2 + 36))^2 = ( (( 3)^2 + 16))^2 (x 7)2 + 36 = (x 3)2 + 16 (x 7)2 (x 3)2 = 16 36 x2 + 49 14x (x2 + 9 6x) = 20 x2 + 49 14x x2 9 + 6x = 20 0 8x + 40 = -20 8x = 20 40 8x = -60 x = ( 60)/( 8) x = 15/2 Thus, Required point = C(x ,0) = (15/2, 0)

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Davneet Singh

Davneet Singh is a graduate from Indian Institute of Technology, Kanpur. He has been teaching from the past 9 years. He provides courses for Maths and Science at Teachoo.