Advertisements
Advertisements
प्रश्न
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.

Advertisements
उत्तर
AB = 24 cm, BC = 7 cm
(i)
AC = `sqrt("AB"^2 + "BC"^2)`
= `sqrt(24^2 + 7^2)`
= `sqrt(576 + 49)`
= `sqrt(625) = 25` cm

(ii)
Area of ΔABC = `1/2 "AB" xx "BC"`
= `1/2 xx 24 xx 7 = 84` cm2
(iii)
BD ⊥ AC
Area ΔABC = `1/2 "AC" xx "BD"`
`84 = 1/2 xx 25 xx "BD"`
⇒ BD = `(84 xx 2)/25 = 168/25 = 6.72` cm
= 6.72 cm ≈ 6.7 cm
APPEARS IN
संबंधित प्रश्न
In triangle ABC; angle A = 90o, side AB = x cm, AC = (x + 5) cm and area = 150 cm2. Find the sides of the triangle.
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 sides of a triangle are 16 cm, 12 cm, and 20 cm. Find :
(i) area of the triangle ;
(ii) height of the triangle, corresponding to the largest side ;
(iii) height of the triangle, corresponding to the smallest side.
The area of an equilateral triangle is numerically equal to its perimeter. Find its perimeter correct to 2 decimal places.
Find the area of a triangle whose base is 3.8 cm and height is 2.8 cm.
Find the area of a right angled triangle whose hypotenuse is 15cm and the base is 9cm.
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.
Find the perimeter of a triangle with sides measuring 10 cm, 14 cm and 15 cm.
A piece of string is 30 cm long. What will be the length of each side if the string is used to form an equilateral triangle?
