CBSE Guess > Papers > Question Papers > Class X > 2009 > Mathematics > Mathematics

Q. 13. Find a relation between x and y if the points (2, 1), (x, y) and (7, 5) are collinear.

Sol .
Let A(2, 1), B(x, y) and C(7, 5) Pts. A, B, C are collinear … (Given)
2(y – 5) + x(5 – 1) + 7(1 – y) = 0
2y – 10 + 5x – 5 + 7 – 7y = 0
5x – 5y – 8 = 0
or
5x – 5y = 8

Q. 14. ABC is an equilateral triangle with side 2a. Find the length of one of its altitudes. 2

Sol .

Mathematics 2009 Question Papers Class X
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					Set 2		Set 2
					Set 3		Set 3