9.5 Mid point Formula
Theorem : If the coordinates of the end points of a segment are (x_{1}, y_{1}) and (x_{2}, y_{2}), then the coordinates of the mid point of this segment is given by the formula :
Example 1
Find the mid point of a segment if A is (6,8) and B is (2, 4).
Solution :
Let (6, 8) be (x_{1}, y_{1}) and
(2, 4) be (x_{2}, y_{2}).
Therefore their mid point M is given as :
Example 2
If the mid point of seg. AB is (3, 8) and A is (12, 1), find coordinates of B.
Solution :
Let the coordinates of B be (x, y). According to the midpoint formula
Therefore
the coordinates of B are (18, 17).
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