solutions of ex.4.1 9th
Answers
Answer:
ok friend. .
Step-by-step explanation:
please like that...❤❤❤
Answer:
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 ₹ x and that of a pen to be ₹ y)
Solution:
Let the cost of a notebook to be = ₹ x
Let the cost of a pen to be = ₹ y
According to the question,
The cost of a notebook is twice the cost of a pen.
i.e., Cost of a notebook = 2 Cost of a pen
x = 2 y
x = 2y
x-2y = 0
x-2y= 0 is the linear equation in two variables to represent the statement ‘The cost of a notebook is twice the cost of a pen’.
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 = 9.3\overline{5}
5
Solution:
2x + 3y = 9.3\overline{5}
5
Re-arranging the equation, we get,
2x + 3y – 9.3\overline{5}
5
= 0
The equation 2x + 3y – 9.3\overline{5}
5
= 0 can be written as,
2x + 3y + (- 9.3\overline{5}
5
) = 0
Now comparing 2x + 3y + (-9.3\overline{5}
5
) = 0 with ax + by + c = 0
We get,
a = 2
b = 3
c = – 9.3\overline{5}
5
(ii) x – y/5 – 10 = 0
ncert solutions for class 9 maths chapter 4 fig 1
(iii) –2x + 3y = 6
Solution:
–2x + 3y = 6
Re-arranging the equation, we get,
–2x + 3y – 6 = 0
The equation –2x + 3y – 6 = 0 can be written as,
(–2)x + 3y +(– 6) = 0
Now comparing (–2)x + 3y +(– 6) = 0 with ax + by + c = 0
We get, a = –2
b = 3
c = -6
(iv) x = 3y
ncert solutions for class 9 maths chapter 4 fig 2
(v) 2x = –5y
Solution:
2x = –5y
Re-arranging the equation, we get,
2x + 5y = 0
The equation 2x + 5y = 0 can be written as,
2x + 5y + 0= 0
Now comparing 2x + 5y + 0= 0 with ax + by + c = 0
We get, a = 2
b = 5
c =0
(vi) 3x + 2 = 0
Solution:
3x + 2 = 0
The equation 3x + 2 = 0 can be written as,
3x + 0y + 2 = 0
Now comparing 3x +0 + 2= 0 with ax + by + c = 0
We get, a = 3
b = 0
c =2
(vii) y – 2 = 0
Solution:
y – 2 = 0
The equation y – 2 = 0 can be written as,
0x + 1y + (–2) = 0
Now comparing 0x + 1y + (–2) = 0with ax + by + c = 0
We get, a = 0
b = 1
c = –2
(viii) 5 = 2x
Solution:
5 = 2x
Re-arranging the equation, we get,
2x = 5
i.e., 2x– 5 = 0
The equation 2x– 5 = 0 can be written as,
2x + 0y – 5 = 0
Now comparing 2x + 0y – 5 = 0 with ax + by + c = 0
We get, a = 2
b = 0
c =5
Step-by-step explanation:
hope it helps
mark as brainlist