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Find the area of a parallelogram ABCD in which AB = 60cm, BC = 40cm and AC = 80 cm. [Given: = 3.87]
Let the sides of the triangle ABC be:
a = 40 cm, b = 80 cm and c = 60 cm
∴ s =
=
=
= 90 cm
Now, by using Heron’s formula we get:
Area of
=
=
=
= 30 × 10
= 300 × 3.87
= 1161 cm2
As we know that, the diagonal of a parallelogram divides it into two triangles of equal areas
∴ Area of parallelogram (ABCD) = 2 × Area of ()
= 2 × 1161
= 2322 cm2
The question consists of two statements namely, Assertion (a) and Reason (R). Please select the correct answer.
Assertion (A) | Reason (R) |
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Assertion(A) | Reason (R) |
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Assertion(A) | Reason (R) |
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Assertion (A) | Reason (R) |
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Assertion (A) | Reason (R) |
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Match the following columns.
Column I | Column II |
(a) The lengths of three sides of a triangle are 26 cm, 28 cm and 30cm. The height corresponding to base 28cm is……cm | (p) 6 |
(b) The area of an equilateral triangle is | (q) 4 |
(c) If the height of an equilateral triangle is | (r) 24 |
(d) Let the base of an isosceles triangle be 6 cm and each of the equal side be 5cm. Then, its height is ….cm | (s) 12 |
The correct answer is :
(a)-…….. (b)-……..
(c)-……… (d)-………