Area of an Isosceles Triangle

Q.

If an isosceles triangle has a perimeter of $18cm$ and base $8cm$, then its area is ___ .

1. $45c{m}^2$

2. $68c{m}^2$

3. $12c{m}^2$

4. $20c{m}^2$

Q. Is the following formula to calculate the area of an isoscles triangle true or false?
$\frac{b}{4}\times \sqrt{4a^2-b^2}$ , where b is the base and a is the length of the equal sides.

1. True
2. False

Q. The perimeter of an isosceles triangle is 32 cm. The ratio of the equal side to its base is 3:2.
Find the area of the triangle.

1. $\sqrt{32}c{m}^2$
2. $32\sqrt{2}c{m}^2$
3. $32c{m}^2$
4. $32\sqrt{4}c{m}^2$

Q.

The perimeter of an isosceles triangle is 32 cm. The ratio of the equal side to its base is 3 : 2. Find the area of the triangle.

Q.

Find the area of an isosceles triangle each of whose equal sides measures 13 cm and whose base measures 20 cm.

Q.

$\text{The base of an isosceles triangle is 16 cm and its area is 48}c{m}^2.\text{The perimeter of the triangle is}\left(a\right)41cm\left(b\right)36cm\left(c\right)48cm\left(d\right)324cm$

Q. Question 8
The area of an isosceles triangle having base 2cm and the length of one of the equal sides 4cm, is

Q. Question 3
Write True or False and justify your answer:

The area of the isosceles triangle is $\frac{5}{4}\sqrt{11}c{m}^2$ if the perimeter is 11cm and the base is 5cm.

Q.

In the given shelf which is right angled at A, AB = AC = 48 inches. Find the area of the shelf.

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1. 1155 sq. inches

2. 1152 sq. inches

3. 1142 sq. inches

4. 1158 sq. inches

Q.

If an isosceles triangle has a perimeter of $18cm$ and base $8cm$, then its area is ___ .

1. $45c{m}^2$

2. $68c{m}^2$

3. $12c{m}^2$

4. $20c{m}^2$