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Find the perimeter and area of the quadrilateral ABCD in which AB = 42 cm, BC = 21 cm, CD = 29 cm, DA = 34 cm and =900.
Firstly, let us calculate the perimeter of the given quadrilateral
Perimeter of quadrilateral ABCD = 34 + 29 + 21 + 42 = 126 cm
We know that,
Area of triangle =
Area of triangle BCD =
= 210 cm2
Now, we have to calculate the area of triangle ABD,
For this, we have
a = 42 cm
b = 20 cm
c = 34 cm
Therefore,
s =
=
= 48 cm
We know that,
Area of triangle =
Therefore,
Area of triangle ABD =
=
=
= 4 × 3 × 2 × 14
= 336 cm2
Hence,
Area of quadrilateral ABCD = Area of triangle ABD + Area of triangle BCD
= 336 + 210
= 546 cm2