Question

Worksheet 2
Fig. 12.13
12
Construct a quadrilateral ABCD in which AB = 4 cm, BC = 3 cm, CD = 3.5 cm
diagonals are AC = 6 cm and BD = 5.5 cm.
2.
Construct a quadrilateral ABCD in which AB = BC = 5 cm, CD = 6 cm, diago
are 7 cm each.
3.
Construct a quadrilateral ABCD in which three sides are 4 cm each and be
diagonals are 6 cm each.
208​

Answer 1

Answer:

Mathematics NCERT Grade 7, Chapter 11: Perimeter and Area- This chapter gives all the details about the perimeter and area of plane figures. Firstly the chapter discusses squares and rectangles.

Perimeter is the distance around a closed figure whereas area is the part of the plane occupied by the closed figure.

The perimeter of the following geometrical shapes are discussed in the first section:

Square

Perimeter of a square = 4 × side

Rectangle

Perimeter of a rectangle = 2 × (length + breadth)

The section is divided into two sub-parts:

1. Triangles as parts of rectangles

2. Generalising for other congruent parts of rectangles

Before moving onto exercise 11.2, the topics Area of triangle and parallelogram are discussed.

Area of a square = side × side

Area of a rectangle = length × breadth

Area of a parallelogram = base × height

Area of a triangle =1/2 × base × h