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A line passes through (x1, y1) and (h, k). If slope of the line is m, show that k – y1 = m (h – x1).

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Question

A line passes through (x1, y1) and (h, k). If slope of the line is m, show that k – y1 = m (h – x1).

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Solution

The slope of the line passing through (x, y) and (h, k) is `(k - y_1)/(h - x_1)`

It is given that the slope of the line is m.

`("k" - "y"_1)/("h" - "x"_1) = "m"`

= k – y1 = m(h – x1)

Hence, k – y1 = m(h – x1)

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Chapter 9: Straight Lines - EXERCISE 9.1 [Page 159]

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NCERT Mathematics [English] Class 11
Chapter 9 Straight Lines
EXERCISE 9.1 | Q 11. | Page 159

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