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Question
In Fig. 14.46, the area of ΔABC (in square units) is
Options
15
10
7.5
2.5
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Solution
The coordinates of A are (1, 3).
∴ Distance of A from the x-axis, AD = y-coordinate of A = 3 units
The number of units between B and C on the x-axis are 5.
∴ BC = 5 units
Now,
Area of ∆ABC = \[\frac{1}{2} \times BC \times AD = \frac{1}{2} \times 5 \times 3 = \frac{15}{2} = 7 . 5\] square units
Thus, the area of ∆ABC is 7.5 square units.
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