Advertisements
Advertisements
Question
Find the area of an isosceles triangle having the base x cm and one side y cm.
Advertisements
Solution
Let us assume triangle ABC be the given isosceles triangle having sides AB = AC and base BC. The area of a triangle ABC, say A having given sides AB and AC equals to y cm and given base BC equals to x cm is given by
`A=1/2 " (Base" xx "Height)"`
Where,
Base = BC = x cm; Height = `sqrt(y^2 -x^2/4`
`A=1/2 " (Base" xx "Height)"`
`=1/2 xx x (sqrt(y^2 -x^2/4))`
`=x/2 (sqrt(y^2 -x^2/4))`
APPEARS IN
RELATED QUESTIONS
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?
The perimeter of an isosceles triangle is 42 cm and its baše is (32) times each of the equal sides. Find the length of each side of the triangle, area of the triangle and the height of the triangle.
The adjacent sides of a parallelogram ABCD measure 34 cm and 20 cm, and the diagonal AC measures 42 cm. Find the area of the parallelogram.
Find the area of the triangle formed by the points
(1, – 1), (– 4, 6) and (– 3, – 5)
Determine whether the sets of points are collinear?
`(-1/2, 3), (-5, 6) and (-8, 8)`
Determine whether the sets of points are collinear?
(a, b + c), (b, c + a) and (c, a + b)
The area of triangle formed by the points (− 5, 0), (0, – 5) and (5, 0) is
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 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.
A field is in the shape of a trapezium having parallel sides 90 m and 30 m. These sides meet the third side at right angles. The length of the fourth side is 100 m. If it costs Rs 4 to plough 1 m2 of the field, find the total cost of ploughing the field.
