मराठी

A Wire When Bent in the Form of a Square Encloses an Area = 576 Cm2. Find the Largest Area Enclosed by the Same Wire When Bent to Form; (I) An Equilateral Triangle. (Ii) a Rectangle Whose Adjacent - Mathematics

Advertisements
Advertisements

प्रश्न

A wire when bent in the form of a square encloses an area = 576 cm2. Find the largest area enclosed by the same wire when bent to form;
(i) an equilateral triangle.
(ii) A rectangle whose adjacent sides differ by 4 cm.

बेरीज
Advertisements

उत्तर

Let a be the length of each side.
a2 = 576
a = 24 cm
4a = 96 cm
Hence length of the wire = 96 cm

(i) For the equilateral triangle,
side = `96/3` = 32 cm

Area = `sqrt3/4`( side )2

        = `sqrt3/4` x 322

        = 256√3 sq.cm

(ii) Let the adjacent side of the rectangle be x and y cm.
Since the perimeter is 96 cm, we have,
2( x + y ) = 96
Hence,
x + y = 48
x - y = 4
x = 26
y = 22
Hence area of the rectangle is = 26 x 22 = 572 sq.cm

shaalaa.com
  या प्रश्नात किंवा उत्तरात काही त्रुटी आहे का?
पाठ 20: Area and Perimeter of Plane Figures - Exercise 20 (B) [पृष्ठ २५६]

APPEARS IN

सेलिना Concise Mathematics [English] Class 9 ICSE
पाठ 20 Area and Perimeter of Plane Figures
Exercise 20 (B) | Q 33 | पृष्ठ २५६

संबंधित प्रश्‍न

Find the area of a quadrilateral one of whose diagonals is 30 cm long and the perpendiculars from the other two vertices are 19 cm and 11 cm respectively. 


The diagonals of a quadrilateral are 16 cm and 13 cm. If they intersect each other at right angles; find the area of the quadrilateral.


The perimeter of a rectangular field is `3/5`km. If the length of the field is twice its width; find the area of the rectangle in sq. meters.


A wire when bent in the form of a square encloses an area of 484 m2. Find the largest area enclosed by the same wire when bent to from:

  1. An equilateral triangle.
  2. A rectangle of length 16 m.

The perimeter of a rhombus is 46 cm. If the height of the rhombus is 8 cm; find its area.


Two adjacent sides of a parallelogram are 24 cm and 18 cm. If the distance between the longer sides is 12 cm; find the distance between the shorter sides.


Two adjacent sides of a parallelogram are 28 cm and 26 cm. If one diagonal of it is 30 cm long; find the area of the parallelogram. Also, find the distance between its shorter sides.


Find the diagonal of a quadrilateral whose area is 756cm2 and the perpendicular from the opposite vertices are 17cm and 19cm.


When proving that a quadrilateral is a parallelogram by using slopes you must find


PQRS is a rectangle formed by joining the points P(– 1, – 1), Q(– 1, 4), R(5, 4) and S(5, – 1). A, B, C and D are the mid-points of PQ, QR, RS and SP respectively. Is the quadrilateral ABCD a square, a rectangle or a rhombus? Justify your answer.


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×