In this page we have *NCERT book Solutions for Class 9th Maths Linear equations in two variables* for
EXERCISE 4.1 on page 68. Hope you like them and do not forget to like , social share
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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.)

Let cost of notebook and a pen be x and y respectively.

Cost of note book = 2 cost of pen

$x = 2y$

$x - 2 y = 0$

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

(i) $2x+3y=9.3\bar{5} $

(ii) $x- \frac {y}{5}-10=0$

(iii) $-2x + 3 y = 6$

(iv) $x = 3y$

(v) $2x = - 5y$

(vi) $3x + 2 = 0$

(vii) $y - 2 = 0$

(viii) $5 = 2x$

(i) $2x+3y=9.3\bar{5} $

=> $2x+3y-9.3\bar{5} =0$

Comparing this equation with $ax + by + c = 0$,

a=2 ,b=3 $c=-9.3\bar{5}$.

Comparing this equation with $ax + by + c = 0$,

a = 1, b =-1/5,c = -10

(iii) $-2x + 3 y = 6$

=> $-2x + 3 y - 6 = 0$

Comparing this equation with $ax + by + c = 0$,

a = -2, b = 3, c = -6

(iv)$x = 3y$

=> $x - 3y + 0 = 0$

Comparing this equation with $ax + by + c = 0$,

a = 1, b = -3, c = 0

(v) $2x = - 5y$

=> $2x + 5y + 0= 0$

Comparing this equation with $ax + by + c = 0$,

a = 2, b = 5, c = 0

(vi) $3x + 2 = 0$

=> $3x + 0.y + 2 = 0$

Comparing this equation with $ax + by + c = 0$,

a = 3, b = 0, c = 2

(vii) $y - 2 = 0$

=> y - 2 = 0

Comparing this equation with $ax + by + c = 0$,

a = 0, b = 1, c = -2

(vii) $5 = 2x$

=> $- 2x + 5 = 0$

Comparing this equation with $ax + by + c = 0$,

a = -2, b = 0, c = 5

**Notes**-
**Ncert Solutions** **Assignments**

Class 9 Maths Class 9 Science

Download Linear Equation Ex 4.1 assignment as pdf