21 A wire when bent
when bent in the form of an equilateral triangle encloses an area of 36 v3 cm.
the area enclosed by the same wire when bent to form:
Find
(i) a square, and
(ii) a rectangle whose length is 2 cm more than its width.
Answers
It's always better to know Key Points before Solving the Question! Here are some Key Points which helps us solve this Question easily
- The Area of an equilateral triangle is given by and The Perimeter of an equilateral triangle is given by . The Area of a Square is given by the expression and The Perimeter of a Square is given by the expression . The Area of a Rectangle is given by the expression and The Perimeter of a Rectangle is given by the expression
First, We will find the Measure of Each Side in the Equilateral Triangle
It is Clearly mentioned Wire bent in the form of an equilateral triangle encloses an area of in the Question
Divide both Sides by the Equation by
Take Square Root on Both Sides of the Equation
Now the Total Length of Wire will be Equal to Perimeter of Wire. Perimeter of Wire = Perimeter of Equilateral Triangle
1) The length of the side of the square is obtained by Dividing Total Length of Wire/Number of Sides in a Square or Total Length of Wire/4
Thus the Area of Square is obtained as follows :
2) The Perimeter of the rectangle should be 36 cm. Thus the relation obtained is . Since the difference between length and breadth is 2 cm, thus the relation obtained is . Thus the values of the length and breadth are calculated as follows :
Subtract 4 cm from Both Sides of the Equation
Divide Both Sides of the Equation by 4
Also
Thus the Area of Rectangle is obtained as follows :