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2 years ago

Find the area of quadrilateral ABCD

Mathematics

1 answer:

andreev551 [17]2 years ago

3 0

Answer:

Step-by-step explanation:

a, b, c

P = a + b + c

Semiperimeter s = $\frac{a+b+c}{2}$

A = $\sqrt{s(s-a)(s-b)(s-c)}$

~~~~~~~~~~~~~~~

$P_{ABC}$ = 4.3 + 2.89 + 6.81 = 14

s = 14 ÷ 2 = 7

$A_{ABC}$ = $\sqrt{7(7-4.3)(7-2.89)(7-6.81)}$ = √14.75901 ≈ 3.84

$P_{BCD}$ = 8.59 + 7.58 + 6.81 = 22.98

s = 22.98 ÷ 2 = 11.49

$A_{BCD}$ = $\sqrt{11.49(11.49-8.59)(11.49-7.58)(11.49-6.81)}$ = √609.7343148 ≈ 24.6928

$A_{ABCD}$ = 3.84 + 24.6928 ≈ <em>28.5</em>

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