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A straight line moves so that the sum of the reciprocals of its intercepts made on axes is constant. Show that the line passes through a fixed point.

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प्रश्न

A straight line moves so that the sum of the reciprocals of its intercepts made on axes is constant. Show that the line passes through a fixed point.

योग
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उत्तर

Intercepts form of a straight line is `x/a + y/b` = 1

Where a and b are the intercepts made by the line on the axes.

Given that: `1/a + 1/b = 1/k`  (say)

⇒ `k/a + k/b` = 1

Which shows that the line is passing through the fixed point (k, k).

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Equations of Line in Different Forms - Equation of Family of Lines Passing Through the Point of Intersection of Two Lines
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अध्याय 10: Straight Lines - Exercise [पृष्ठ १७९]

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एनसीईआरटी एक्झांप्लर Mathematics Exemplar [English] Class 11
अध्याय 10 Straight Lines
Exercise | Q 16 | पृष्ठ १७९

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