Advertisements
Advertisements
Question
Find the area of a triangle, whose sides are :
21 m, 28 m, and 35 m
Advertisements
Solution
Sides of ∆ are
a = 21 m
b = 28 m
c = 35 m
S = `(a + b + c)/2 = (21 + 28 + 35)/2`
= `84/2 = 42`
area of Δ = `sqrt(S(S - a)(S - b)(S - c))`
= `sqrt(42(42 - 21)(42 - 28)(42 - 35))`
= `sqrt(42 xx 21 xx 14 xx 7)`
= `sqrt(7 xx 3 xx 2 xx 3 xx 7 xx 2 xx 7 xx 7)`
= `sqrt(7 xx 7 xx 7 xx 7 xx 3 xx 3 xx 2 xx 2)`
= `7 xx 7 xx 3 xx 2 = 294 "m"^2`
APPEARS IN
RELATED QUESTIONS
If the difference between the sides of a right-angled triangle is 3 cm and its area is 54 cm2; find its perimeter.
The sides of a triangular field are in the ratio 5: 3: 4 and its perimeter is 180 m. Find:
- its area.
- the altitude of the triangle corresponding to its largest side.
- the cost of leveling the field at the rate of Rs. 10 per square meter.
The base and the height of a triangle are in the ratio 4: 5. If the area of the triangle is 40 m2; find its base and height.
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.
Find the area of the right-angled triangle with a hypotenuse of 40 cm and one of the other two sides of 24 cm.
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 and the area of a right angled triangle whose sides are 6 feet, 8 feet and 10 feet
Find the perimeter of An equilateral triangle with side 6 cm
The scalene triangle has 40 cm as its perimeter and whose two sides are 13 cm and 15 cm, find the third side
Find the perimeter of the triangle, whose sides are 13 cm, 5 cm and 14 cm
