Linear Equations in Two Variables - Solutions
CBSE Class 9 Mathematics
NCERT Solutions
CHAPTER 4
Linear Equations in Two Variables(Ex. 4.1)
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. Let the cost of a notebook be.
Let the cost of a pen be.
We need to write a linear equation in two variables to represent the statement, “Cost of a notebook is twice the cost of a pen”.
Therefore, we can conclude that the required statement will be= x -2y = 0
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)
(ii)
(iii)
(iv)
(v)
(vi)
(vii)
(viii)
Ans. (i)
We need to express the linear equationin the form ax + by + c = 0 and indicate the values of a, b and c.
can also be written as
We need to compare the equationwith the general equation ax + by + c = 0, to get the values of a, b and c.
Therefore, we can conclude that.
(ii)
We need to express the linear equationin the form ax + by + c = 0 and indicate the values of a, b and c.
can also be written as
We need to compare the equationwith the general equation ax + by + c = 0, to get the values of a, b and c.
Therefore, we can conclude that.
(iii)
We need to express the linear equationin the form ax + by + c = 0 and indicate the values of a, b and c.
can also be written as
We need to compare the equationwith the general equation ax + by + c = 0, to get the values of a, b and c.
Therefore, we can conclude that.
(iv)
We need to express the linear equationin the form ax + by + c = 0 and indicate the values of a, b and c.
can also be written as
We need to compare the equationwith the general equation ax + by + c = 0, to get the values of a, b and c.
Therefore, we can conclude that.
(v)
We need to express the linear equationin the form ax + by + c = 0 and indicate the values of a, b and c.
can also be written as
We need to compare the equationwith the general equation ax + by + c = 0, to get the values of a, b and c.
Therefore, we can conclude that.
(vi)
We need to express the linear equationin the form ax + by + c = 0 and indicate the values of a, b and c.
can also be written as
We need to compare the equationwith the general equation ax + by + c = 0, to get the values of a, b and c.
Therefore, we can conclude that.
(vii)
We need to express the linear equationin the form ax + by + c = 0 and indicate the values of a, b and c.
can also be written as
We need to compare the equationwith the general equation ax + by + c = 0, to get the values of a, b and c.
Therefore, we can conclude that.
(viii)
We need to express the linear equationin the form ax + by + c = 0 and indicate the values of a, b and c.
can also be written as
We need to compare the equationwith the general equation ax + by + c = 0, to get the values of a, b and c.
Therefore, we can conclude that.