हिंदी

If the diagonal d of a quadrilateral is doubled and the heights h1 and h2 falling on d are halved, then the area of quadrilateral is ______.

Advertisements
Advertisements

प्रश्न

If the diagonal d of a quadrilateral is doubled and the heights h1 and h2 falling on d are halved, then the area of quadrilateral is ______.

रिक्त स्थान भरें
Advertisements

उत्तर

If the diagonal d of a quadrilateral is doubled and the heights h1 and h2 falling on d are halved, then the area of quadrilateral is `underlinebb(1/2(h_1 + h_2)d)`.

Explanation:

Let ABCD be a quadrilateral, where h1 and h2 are altitudes on the diagonal BD = d.

Then, area of quadrilateral `ABCD = 1/2(h_1 + h_2) xx BD`

If altitudes are halved and the diagonal is doubled, then

Area of quadrilateral `ABCD = 1/2(h_1/2 + h_2/2) xx 2d`

= `1/2((h_1 + h_2)/2) xx 2d`

= `1/2(h_1 + h_2) xx d`

shaalaa.com
  क्या इस प्रश्न या उत्तर में कोई त्रुटि है?
अध्याय 11: Mensuration - Exercise [पृष्ठ ३५०]

APPEARS IN

एनसीईआरटी एक्झांप्लर Mathematics [English] Class 8
अध्याय 11 Mensuration
Exercise | Q 38. | पृष्ठ ३५०

वीडियो ट्यूटोरियलVIEW ALL [1]

संबंधित प्रश्न

The area of a rectangular is 640 m2. Taking its length as x cm; find in terms of x, the width of the rectangle. If the perimeter of the rectangle is 104 m; find its dimensions.


The figure given below shows the cross-section of a concrete structure. Calculate the area of cross-section if AB = 1.8 cm, CD = 0.6 m, DE = 0.8 m, EF = 0.3 m and AF = 1.2 m.


The width of a rectangular room is `4/7`of its length, x, and its perimeter is y. Write an equation connecting x and y. Find the length of the room when the perimeter is 4400 cm.


The length of a rectangular verandah is 3 m more than its breadth. The numerical value of its area is equal to the numerical value of its perimeter.

(i) Taking x as the breadth of the verandah, write an equation in x that represents the above statement

(ii) Solve the equation obtained in (i) above and hence find the dimensions of the verandah. 


Sum of the areas of two squares is 400 cm2. If the difference of their perimeters is 16 cm, find the sides of the two squares. 


A quadrilateral field of unequal has a longer diagonal with 140m. The perpendiculars from opposite vertives upon this diagonal are 20m and 14m. Find the area of the field.


In the following, find the value of ‘a’ for which the given points are collinear

(2, 3), (4, a) and (6, – 3)


Find the value of k, if the area of a quadrilateral is 28 sq. units, whose vertices are (– 4, – 2), (– 3, k), (3, – 2) and (2, 3)


The quadrilateral swimming pool shown is surrounded by concrete patio. Find the area of the patio


If vertices of a quadrilateral are at A(– 5, 7), B(– 4, k), C(– 1, – 6) and D(4, 5) and its area is 72 sq. units. Find the value of k.


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×