Question

two sides of a parallelogram are 10 cm and 7 cm one of its diagonal is 13 cm. find the area

Answer 1

hope it helps you see it on the above pic

Answer 2

Answer:

The area of parallelogram is 69.2820 sq.cm.

Step-by-step explanation:

We are given that two sides of a parallelogram are 10 cm and 7 cm one of its diagonal is 13 cm.

Refer the attached figure

ABCD is parallelogram

AB =CD = 10 cm

AD = CB = 7 cm

Diagonal BD = 13 cm

Diagonal divides the parallelogram into two equal triangles

We will find the area of triangle ABD

We will use herons formula :

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

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

a= 10

b = 7

c = 13

Substitute the values in the formula :

$s=\frac{10+7+13}{2}$

$s=\frac{10+7+13}{2}$

$Area = \sqrt{15(15-10)(15-7)(15-13)}$

$Area = 34.6410161514$

Area of parallelogram = $2 \times \text{Area of triangle }= 2 \times 34.6410161514=69.2820 cm^2$

Hence the area of parallelogram is 69.2820 sq.cm.