Advertisements
Advertisements
प्रश्न
Find the area and the perimeter of quadrilateral ABCD, given below; if AB = 8 cm, AD = 10 cm, BD = 12 cm, DC = 13 cm and ∠DBC = 90°.
Advertisements
उत्तर
Given, AB = 8 cm, AD = 10 cm, BD = 12 cm, DC = 13 cm and ∠DBC = 90°
BC = `sqrt("DC"^2 - "BD"^2)`
= `sqrt( 13^2 - 12^2 )`
= 5 cm
Hence, perimeter = 8 + 10 + 13 + 5 = 36 cm
Area of ΔABD, `sqrt("s"("s"-"a")("s"-"b")("s"-"c"))`
Here, s = `("a"+"b"+"c")/2`
= `(10+12+8)/2`
= `30/2`
= 15 cm
ΔABD = `sqrt( 15( 15 - 8 )( 15 - 10 )( 15 - 12 ))`
= `sqrt( 15 xx 7 xx 5 xx 3 )`
= `15sqrt7`
= 39.7
Area of ΔBDC,
ΔBDC = `1/2` × 12 × 5
= 30
Now,
Area of ABCD = area of ΔABD + area of ΔBDC
= 39.7 + 30
= 69.7 sq.cm
APPEARS IN
संबंधित प्रश्न
Find the area of a triangle whose sides are 18 cm, 24 cm, and 30 cm. Also, find the length of altitude corresponding to the largest side of the triangle.
Calculate the area and the height of an equilateral triangle whose perimeter is 60 cm.
The length of the sides of a triangle are in the ratio 3: 4: 5. Find the area of the triangle if its perimeter is 144 cm.
The area of an equilateral triangle is 36`sqrt3` sq. cm. Find its perimeter.
The given figure shows a right-angled triangle ABC and an equilateral triangle BCD. Find the area of the shaded portion.

Find the area of a triangle, whose sides are :
10 cm, 24 cm, and 26 cm
Find the area of a triangle, whose sides are :
21 m, 28 m, and 35 m
The lengths of the sides of a triangle are in the ratio 4: 5 : 3 and its perimeter is 96 cm. Find its area.
The perimeter of a triangle is 72cm and its sides are in the ratio 3:4:5. Find its area and the length of the altitude corresponding to the longest side.
From one vertex of an equilateral triangle with side 40 cm, an equilateral triangle with 6 cm side is removed. What is the perimeter of the remaining portion?
