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If you're good at trig please help meeeee
Show full working out pls

If you're good at trig please help meeeee Show full working out pls-example-1
User Bluuf
by
5.0k points

1 Answer

4 votes

Area of any quadilateral = 1/2 × product of diagonals

Area = 1/2 × 24 × 18 = 216 cm²

We can find the length of sides using cosine rule.

It states :

C² = a² + b² - 2ab × cosc

Where a, b are the two sides and c is the angle between them . C is the side opposite to tt angle.

C²= 9² + 12² - 2 × 9 × 12 × cos40⁰

C² = 81 + 144 - 2 × 9 × 12 × 0.8

C² = 225- 172.8

C=
√(52.2)

C=7.2 cm

Thus one side = 7.2 cm

Similarly in other triangle

C² = 12² + 9² - 2 × 12 × 9 × cos140⁰

C² = 12² + 9² - 2 × 12 × 9 × -0.8

C² = 144 + 81 + 172.8

C² =
√(235 + 172.8)

C = 20.2 cm

Hence the 2 sides are 7.2 cm and 20.2 cm . Other sides are opposite to them and thus have same measure

User Amal Antony
by
5.3k points
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