Advertisements
Advertisements
प्रश्न
A triangular shaped glass with vertices at A(– 5, – 4), B(1, 6) and C(7, – 4) has to be painted. If one bucket of paint covers 6 square feet, how many buckets of paint will be required to paint the whole glass, if only one coat of paint is applied
Advertisements
उत्तर
Given the vertices of the triangular glass is A (– 5, – 4), B (1, 6), and C (7, – 4)
Area of triangle ACB = `1/2[(x_1y_2 + x_2y_3 + x_3y_1) - (x_2y_1 + x_3y_2 + x_1y_3)]`

= `1/2[(20 + 42 - 4) - (-28 - 4 - 30)]`
= `1/2[58 - (- 62)]`
= `1/2 [58 + 62]`
= `1/2 xx 120`
= 60 sq. feet
Number of cans to paint 6 square feet = 1
∴ Number of cans = `60/6` = 10
⇒ Number of cans = 10
APPEARS IN
संबंधित प्रश्न
A traffic signal board, indicating ‘SCHOOL AHEAD’, is an equilateral triangle with side ‘a’. Find the area of the signal board, using Heron’s formula. If its perimeter is 180 cm, what will be the area of the signal board?
A triangle and a parallelogram have the same base and the same area. If the sides of the triangle are 13 cm, 14 cm and 15 cm and the parallelogram stands on the base 14 cm, find the height of the parallelogram.
Find the area of a triangle whose base and altitude are 5 cm and 4 cm respectively.
Find the area of a triangle whose sides are 3 cm, 4 cm and 5 cm respectively.
Find the area of the triangle formed by the points
(–10, –4), (–8, –1) and (–3, –5)
Find the area of an equilateral triangle whose perimeter is 180 cm
An advertisement board is in the form of an isosceles triangle with perimeter 36 m and each of the equal sides are 13 m. Find the cost of painting it at ₹ 17.50 per square metre.
The sides of a quadrilateral ABCD are 6 cm, 8 cm, 12 cm and 14 cm (taken in order) respectively, and the angle between the first two sides is a right angle. Find its area.
A rhombus shaped sheet with perimeter 40 cm and one diagonal 12 cm, is painted on both sides at the rate of Rs 5 per m2. Find the cost of painting.
How much paper of each shade is needed to make a kite given in the following figure, in which ABCD is a square with diagonal 44 cm.
