Advertisements
Advertisements
рдкреНрд░рд╢реНрди
Find the area of a quadrilateral ABCD in which AB = 42 cm, BC = 21 cm, CD = 29 cm, DA =34 cm and diagonal BD =20 cm.
рдЙрддреНрддрд░
Given that
Sides of a quadrilateral are AB = 42 cm, BC = 21 cm, CD = 29 cm
DA = 34 cm and diagonal BD = 20 cm
Area of quadrilateral = area of ΔADB + area of ΔBCD.
Now, area of ΔABD
Perimeter of ΔABD
We know that
⇒ S = `1/2`(ЁЭР┤ЁЭР╡+ЁЭР╡ЁЭР╖+ЁЭР╖ЁЭР┤)
= `1/2`(34+42+20)=96
=`96/2`
= 48 ЁЭСРЁЭСЪ
Area of ΔABD = `sqrt(S(S-AB)(S-BD)(S-DA))`
`=sqrt(48(48-42)(48-20)(48-34))`
`=sqrt(48(14)(6)(28)`
`=336cm^2`
Also for area of ΔBCD,
Perimeter of ΔBCD
`2s = BC + CD + BD`
`⇒S=1/2(29+21+20)+35cm`
By using heron’s formulae
Area of ΔBCD =`sqrt(s(s-bc)(s-cd)(s-db))`
`=sqrt(35(35-21)(53-29)(35-20))`
`=sqrt(210xx210)cm^2`
`= 210cm^2`
∴ Area of quadrilateral ABCD = 336 + 210 = 546 `cm^2`
APPEARS IN
рд╕рдВрдмрдВрдзрд┐рдд рдкреНрд░рд╢реНтАНрди
A traffic signal board, indicating ‘SCHOOL AHEAD’, is an equilateral triangle with side ‘a’. Find the area of the signal board, using Heron’s formula. If its perimeter is 180 cm, what will be the area of the signal board?
The perimeter of a triangular field is 240 dm. If two of its sides are 78 dm and 50 dm, find the length of the perpendicular on the side of length 50 dm from the opposite vertex.
The adjacent sides of a parallelogram ABCD measure 34 cm and 20 cm, and the diagonal AC measures 42 cm. Find the area of the parallelogram.
A man walks near a wall, such that the distance between him and the wall is 10 units. Consider the wall to be the Y-axis. The path travelled by the man is
The sides of the triangular ground are 22 m, 120 m and 122 m. Find the area and cost of levelling the ground at the rate of тВ╣ 20 per m2
An advertisement board is in the form of an isosceles triangle with perimeter 36 m and each of the equal sides are 13 m. Find the cost of painting it at тВ╣ 17.50 per square metre.
The perimeter of an equilateral triangle is 30 cm. The area is
An isosceles right triangle has area 8 cm2. The length of its hypotenuse is ______.
A field in the form of a parallelogram has sides 60 m and 40 m and one of its diagonals is 80 m long. Find the area of the parallelogram.
A design is made on a rectangular tile of dimensions 50 cm × 70 cm as shown in the following figure. The design shows 8 triangles, each of sides 26 cm, 17 cm and 25 cm. Find the total area of the design and the remaining area of the tile.