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The area of an equilateral triangle is cm^{2}. Its height is-
It is given in the question that,
Area of an equilateral triangle = 81 cm^{2}
Let a be the side of the triangle and h be the height
We know that,
Area of an equilateral triangle =
81 =
a^{2} = 81 × 4
a = 18
Also, Area of triangle =
81
h =
h = 9 cm
Hence, option (a) is correct
The question consists of two statements namely, Assertion (a) and Reason (R). Please select the correct answer.
Assertion (A) | Reason (R) |
Area of an equilateral triangle having each side equal to 4cm is sq cm. | Area of an equilateral triangle having each side a is a^{2} sq units. |
The question consists of two statements namely, Assertion (a) and Reason (R). Please select the correct answer.
Assertion(A) | Reason (R) |
The area of an isosceles triangle having base = 8cm and each of the equal sides = 5cm is 12cm^{2}. | The area of an isosceles triangle having each of the equal sides as a and base =b is . |
The question consists of two statements namely, Assertion (a) and Reason (R). Please select the correct answer.
Assertion(A) | Reason (R) |
The area of an equilateral triangle having side 4cm is 3cm^{2} | The area of an equilateral triangle having each side a is (a^{2}) sq units. |
The question consists of two statements namely, Assertion (a) and Reason (R). Please select the correct answer.
Assertion (A) | Reason (R) |
The sides of the triangle ABC are in the ratio 2 : 3 : 4 and its perimeter is 36 cm. Then ar(Δ ABC) = cm^{2}. | If 2s = (a + b +c) where a, b, c are the sides of the triangle, then its area is = . |
The question consists of two statements namely, Assertion (a) and Reason (R). Please select the correct answer.
Assertion (A) | Reason (R) |
The area of an isosceles triangle having base = 24 cm and each of the equal sides equal to 13cm is 60cm^{2}. | If 2s = (a + b+ c) where a, b, c are the sides of a triangle, then area = . |
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 cm^{2}. The perimeter of the triangle is…..cm | (q) 4 |
(c) If the height of an equilateral triangle is cm, then each side of the triangle measures …. Cm | (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)-………