NCERT Solutions Class 9 Maths Chapter 4 – LINEAR EQUATIONS IN TWO VARIABLES EX 4.1

Que.1 The cost of a notebook is twice the cost of a pen. Write a linear equation in two variables to represent this statement.

(Take the cost of a notebook to be Rs. x and that of a pen to be Rs. y).

Ans.

Suppose that the cost of notebook = x

the cost of pen = y

As per question,

⇒  x= 2y

⇒  x – 2y = 0

Que.2. Express the following linear equations in the form ax + by + c = 0 and indicate the values of a, b and c in each case:

(i) 2x + 3y = 9.35

(ii) x –5y– 10 = 0

(iii) –2x + 3y = 6

(iv) x = 3y

(v) 2x = –5y

(vi) 3x + 2 = 0

(vii) y – 2 = 0

(viii) 5 = 2x

ANS.