Q7 of 319 Page 23

Prove that the line y - x + 2 = 0 divides the join of points (3,-1) and (8, 9) in the ratio 2:3

Assuming:

y – x +2 = 0 divides the line joining the points (3, -1) and (8, 9) at the point P in the ratio k : 1


To prove:


Line y - x + 2 = 0 divides the join of points (3,-1) and (8, 9) in the ratio 2:3


Explanation:


P


P lies on the y – x +2 = 0


Therefore,



⇒ -1 + 9k – 3 – 8k +2k + 2 = 0


⇒ 3k = 2


⇒ k


Hence Proved, the line y – x +2 = 0 divides the line joining the points (3, -1) and (8, 9) in the ratio 2 : 3


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