Advertisements
Advertisements
प्रश्न
Find the area of a quadrilateral ABCD in which AB = 3 cm, BC = 4 cm, CD = 4 cm, DA = 5 cm and AC = 5 cm.
Advertisements
उत्तर

For ΔABC,
AC2 = AB2 + BC2
(5)2 = (3)2 + (4)2
Therefore, ΔABC is a right-angled triangle, right-angled at point B.
Area of ΔABC`= 1/2xxABxxBC=1/2xx3xx4=6 cm^2`
For ΔADC,
Perimeter = 2s = AC + CD + DA = (5 + 4 + 5) cm = 14 cm
s = 14/2 = 7 cm
By Heron’s formula,
`"Area of triangle "=sqrt(s(s-a)(s-b)(s-c))`
`"Area of "triangle ADC=[sqrt(7(7-5)(7-5)(7-4))]cm^2`
`=(sqrt(7xx2xx2xx3))cm^2`
`=2sqrt21 cm^2`
= (2 x 4.583) cm2
= 9.166 cm2
Area of ABCD = Area of ΔABC + Area of ΔACD
= (6 + 9.166) cm2
= 15.166 cm2
= 15.2 cm2 (approximately)
संबंधित प्रश्न
A floral design on a floor is made up of 16 tiles which are triangular, the sides of the triangle being 9 cm, 28 cm and 35 cm (see the given figure). Find the cost of polishing the tiles at the rate of 50p per cm2.

Area of PQRS = Area of PQR + Area of ΔPQS = (6+9.166)𝑐𝑚2=15.166𝑐𝑚2
Find the area of a quadrilateral ABCD in which AD = 24 cm, ∠BAD = 90° and BCD forms an equilateral triangle whose each side is equal to 26 cm. (Take √3 = 1.73)
Find the area of an equilateral triangle having each side x cm.
Let Δ be the area of a triangle. Find the area of a triangle whose each side is twice the side of the given triangle.
The base of an isosceles right triangle is 30 cm. Its area is
The sides of a triangle are 50 cm, 78 cm and 112 cm. The smallest altitude is
In the given figure, the ratio AD to DC is 3 to 2. If the area of Δ ABC is 40 cm2, what is the area of Δ BDC?

The area of an equilateral triangle with side `2sqrt(3)` cm is ______.
The area of an isosceles triangle having base 2 cm and the length of one of the equal sides 4 cm, is ______.
