Advertisements
Advertisements
प्रश्न
Find the area of the triangle formed by the points
(–10, –4), (–8, –1) and (–3, –5)
Advertisements
उत्तर
Let the vertices be A(–10, –4), B(–8, –1) and C(–3, –5)

Area of ∆ABC = `1/2[(x_1y_2 + x_2y_3 + x_3y_1) - (x_2y_1 + x_3y_2 + x_1y_3)]`
= `1/2[(50 + 3 + 32) - (12 + 40 + 10)]`
= `1/2[((-8 xx -4) + (-10 xx -5) + (-3 xx -1)),(-(-1 xx -10) + (-4 xx -3) + (-5 xx -8))]`
= `1/2[85 - 62]`
= `1/2[23]`
= 11.5
Area of ∆ACB = 11.5 sq.units
APPEARS IN
संबंधित प्रश्न
The triangular side walls of a flyover have been used for advertisements. The sides of the walls are 122m, 22m, and 120m (see the given figure). The advertisements yield an earning of ₹ 5000 per m2 per year. A company hired one of its walls for 3 months. How much rent did it pay?

The lengths of the sides of a triangle are in the ratio 3 : 4 : 5 and its perimeter is 144 cm. Find the area of the triangle and the height corresponding to the longest side.
Sides of a triangle are cm 45 cm, 39 cm and 42 cm, find its area.
Some measures are given in the adjacent figure, find the area of ☐ABCD.

Find the areas of the given plot. (All measures are in metres.)

Find the area of triangle AGF
The area of triangle formed by the points (− 5, 0), (0, – 5) and (5, 0) is
The area of the isosceles triangle is `5/4 sqrt(11)` cm2, if the perimeter is 11 cm and the base is 5 cm.
The cost of levelling the ground in the form of a triangle having the sides 51 m, 37 m and 20 m at the rate of Rs 3 per m2 is Rs 918.
The triangular side walls of a flyover have been used for advertisements. The sides of the walls are 13 m, 14 m and 15 m. The advertisements yield an earning of Rs 2000 per m2 a year. A company hired one of its walls for 6 months. How much rent did it pay?
