Example 4 - Chapter 2 Class 9 - Introduction to Linear Polynomials (Ganita Manjari

Transcript

Example 4 The perimeter of a square of side x is 4x, which is a linear polynomial in the variable x. Find the perimeter of squares with sides 1 cm, 1.5 cm, 2 cm, 2.5 cm and 3 cm. What will happen to the perimeters if the sides increase by 0.5 cm? Let’s consider a square of side x Now, Perimeter of square = Sum of all sides = x + x + x + x = 4x Now, to find perimeter of square of any side, we just put value of side in the formula Finding perimeter of squares with sides 1 cm, 1.5 cm, 2 cm, 2.5 cm and 3 cm Perimeter would be Perimeter of square of side 1 cm = 4 × 1 = 4 cm Perimeter of square of side 1.5 cm = 4 × 1.5 = 6 cm Perimeter of square of side 2 cm = 4 × 2 = 8 cm Perimeter of square of side 2.5 cm = 4 × 2.5 = 10 cm Perimeter of square of side 3 cm = 4 × 3 = 12 cm We observe that Every time the side length increases by 0.5 cm, the perimeter increases by exactly 2 cm (because 4 × 0.5 = 2) This constant change is the hallmark of a linear pattern!