Telangana SCERT Solution Class IX (9) Math Chapter 6 Linear Equations in Two Variables Exercise 6.1
(1)(i) 8x + 5y – 3 = 0
a = 8; b = 5; c = -3
(ii) 28x + 35y = -7
Or, 28x – 35y + 7 = 0
Or, 7(4x – 5y + 1) = 0
Or, 4x – 5y + 1 = 0
a = 4; b = -5; c = 1
(iii) 93x = 12 – 15y
Or, 93x + 15y – 12 = 0
Or, 3(31x + 5y – 4) = 0
Or, 31x + 5y – 4 =0
a = 31; b = 5; c = -4
(iv) 2x = – 5y
Or, 2x – 5y + 0 = 0
a = 2; b = -5; c = 0
(vii) 3x + 5y = 12
Or, 3x + 5y – 12 = 0
a = 3; b = 5 ; c = – 12
(2) (i) 2x = 5
Or, 2x + 0y – 5 = 0
a = 2; b = 0; c = -5
(ii) y – 2 = 0
Or, 0x + y – 2 = 0
a = 0; b = 1; c = -2
(3.) Express the following statements as a linear equation in two variables.
(i) The sum of two numbers is 34.
(ii) The cost of a ball pen is ` 5 less than half the cost of a fountain pen.
(iii) Bhargavi got 10 more marks than double the marks of Sindhu.
(iv) The cost of a pencil is ` 2 and a ball point pen is ` 15. Sheela pays ` 100
for the pencils and pens she purchased.
(v) Yamini and Fatima of class IX together contributed ` 200/- towards the Prime
Minister’s Relief Fund.
(vi) The sum of a two digit number and the number obtained by reversing the order of its digits is 121. If the digits in unit’s and ten’s place are ‘x’ and ‘y’ respectively
Solution:
(3) (i) Sum of two numbers is 34
Linear equation in two variable => x + y = 34
(ii) Let,
Cost of ball pen be X
Cost of fountain pen be y
X = ½ x y – 5
Or, x – (y )/2 + 5 = 0
Or, 2x – y + 10 = 0
(iii) Let,
Bhargavi marks be x
Sindhus marks be y
∴ x = 2y + 10
Or, x – 2y – 10 = 0