Advertisements
Advertisements
प्रश्न
The lengths of the sides of a triangle are in the ratio 4: 5 : 3 and its perimeter is 96 cm. Find its area.
Advertisements
उत्तर
Let the sides of the triangle ABC be 4x, 5x and 3x
Let AB = 4x, AC = 5x and BC = 3x
Perimeter = 4x + 5x + 3x = 96
=> 12x = 96
⇒ x = `96/12`

∴ x = 8
∴ Sides are
BC = 3(8) = 24 cm, AB = 4(8) = 32 cm,
AC = 5(8) = 40 cm
Since (AC)2 = (AB)2 + (BC)2 [∵ (5x)2 = (3x)2 + (4x)2]
∴ By Pythagorus Theorem, ∠B = 90°
∴ Area of ΔABC = `1/2 ("BC")("AB") = 1/2 (24)(32)`
= `12 xx 32 = 384 "cm"^2`
APPEARS IN
संबंधित प्रश्न
The area of an equilateral triangle is 36`sqrt3` sq. cm. Find its perimeter.
Find the area of an isosceles triangle with perimeter is 36 cm and the base is 16 cm.
The base of a triangular field is three times its height. If the cost of cultivating the field at ₹ 36.72 per 100 m2 is ₹ 49,572; find its base and height.
The perimeter of a triangle is 450 m and its side are in the ratio 12: 5: 13. Find the area of the triangle.
A field is in the shape of a quadrilateral ABCD in which side AB = 18 m, side AD = 24 m, side BC = 40m, DC = 50 m and angle A = 90°. Find the area of the field.
Use the information given in the adjoining figure to find :
(i) the length of AC.
(ii) the area of an ∆ABC
(iii) the length of BD, correct to one decimal place.

The base of a triangle field and its height are in the ratio 2:5. If the cost of cultivating the field at Rs.42 per sq. m is Rs.7560, find its base and height.
The table given below contains some measures of the triangle. Find the unknown values.
| Side 1 | Side 2 | Side 3 | Perimeter |
| ? | 8 m | 3 m | 17 m |
A piece of wire is 36 cm long. What will be the length of each side if we form an equilateral triangle
Find the perimeter of a triangle with sides measuring 10 cm, 14 cm and 15 cm.
