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NCERT Solutions for Linear equations Class 8 Mathematics Chapter 2 CBSE Part 3





In this page we have NCERT Solutions for Linear equations Class 8 Mathematics for EXERCISE 3 . Hope you like them and do not forget to like , social share and comment at the end of the page.
Question 1
Solve and check result: 3x = 2x + 18
Answer
 3x = 2x + 18
Transposing 2x to L.H.S, we obtain
3x − 2x = 18
x = 18
Let us evaluate both the LHS and RHS for validate the answer
L.H.S = 3x = 3 × 18 = 54
R.H.S = 2x + 18 = 2 × 18 + 18 = 36 + 18 = 54
L.H.S. = R.H.S.
It proves that result is correct
Question 2
 Solve and check result: 5t − 3 = 3t − 5
Answer
5t − 3 = 3t − 5
Transposing  3t to L.H.S and −3 to R.H.S, we obtain
5t − 3t = −5 − (−3)
2t = −2
Dividing both sides by 2
t = −1
Let us evaluate both the LHS and RHS for validate the answer
L.H.S = 5t − 3 = 5 × (−1) − 3 = −8
R.H.S = 3t − 5 = 3 × (−1) − 5 = − 3 − 5 = −8
L.H.S. = R.H.S.
It proves that result is correct
Question 3
Solve and check result
 5x + 9 = 5 + 3x
Answer
 5x + 9 = 5 + 3x
Transposing 3x to L.H.S and 9 to R.H.S, we obtain
5x − 3= 5 − 9
2x = −4
Dividing both sides by 2, we obtain
= −2
Let us evaluate both the LHS and RHS for validate the answer
L.H.S = 5x + 9 = 5 × (−2) + 9 = −1
R.H.S = 5 + 3x = 5 + 3 × (−2)  = −1
L.H.S. = R.H.S.
It proves that result is correct
Question 4
 Solve and check result:
4z + 3 = 6 + 2z
Answer
 4z + 3 = 6 + 2z
Transposing 2z to L.H.S and 3 to R.H.S, we obtain
4z − 2z = 6 − 3
2z = 3
Dividing both sides by 2, we obtain
z=3/2
Let us evaluate both the LHS and RHS for validate the answer
L.H.S = 4z + 3 = 4 × (3/2) + 3 = 6 + 3 = 9
R.H.S = 6 + 2z = 6 + 2 × (3/2) = 6 + 3 = 9
L.H.S. = R.H.S.
It proves that result is correct
Question 5
 Solve and check result:
 2x − 1 = 14 − x
Answer
 2x − 1 = 14 − x
Transposing x to L.H.S and 1 to R.H.S, we obtain
2x + x = 14 + 1
3x = 15
Dividing both sides by 3, we obtain
x = 5
Let us evaluate both the LHS and RHS for validate the answer
L.H.S = 2x − 1 = 2 × (5) − 1 = 10 − 1 = 9
R.H.S = 14 − x = 14 − 5 = 9
L.H.S. = R.H.S.
It proves that result is correct

Question 6
Solve and check result:
8x + 4 = 3(x − 1) + 7
Answer
 8x + 4 = 3(− 1) + 7
8x + 4 = 3x − 3 + 7
Transposing 3x to L.H.S and 4 to R.H.S, we obtain
8− 3x = − 3 + 7 − 4
5x = − 7 + 7
5x=0
x=0
Let us evaluate both the LHS and RHS for validate the answer
L.H.S = 8x + 4 = 8 × (0) + 4 = 4
R.H.S = 3(x − 1) + 7 = 3 (0 − 1) + 7 = − 3 + 7 = 4
L.H.S. = R.H.S.
It proves that result is correct
Question 7- 
Solve and check result: NCERT Solutions for Linear equations Class 8 Mathematics Chapter 2
Answer
NCERT Solutions for Linear equations Class 8 Mathematics Chapter 2
Multiplying both sides by 5, we obtain
5x = 4(x + 10)
5x = 4x + 40
Transposing 4x to L.H.S, we obtain
5x − 4x = 40
x = 40
Let us evaluate both the LHS and RHS for validate the answer
L.H.S = x = 40
R.H.S = = 40
L.H.S. = R.H.S.
It proves that result is correct
Question 8
Solve and check result: NCERT Solutions for Linear equations Class 8 Mathematics Chapter 2
Answer
NCERT Solutions for Linear equations Class 8 Mathematics Chapter 2
Transposing  7x/15 on LHS and 1 on RHS
NCERT Solutions for Linear equations Class 8 Mathematics Chapter 2
Multiplying by 15 on both sides
10x-7x= 30
3x=30
Dividing by 3 on both the sides
x=10
Let us evaluate both the LHS and RHS for validate the answer
L.H.S =NCERT Solutions for Linear equations Class 8 Mathematics Chapter 2 =23/3
R.H.S=NCERT Solutions for Linear equations Class 8 Mathematics Chapter 2 =23/3
L.H.S. = R.H.S.
It proves that result is correct
Question 9
 Solve and check result
NCERT Solutions for Linear equations Class 8 Mathematics Chapter 2
Answer
NCERT Solutions for Linear equations Class 8 Mathematics Chapter 2
Transposing y to L.H.S and 5/3 to R.H.S, we obtain
NCERT Solutions for Linear equations Class 8 Mathematics Chapter 2
3y=21/3
3y=7
Dividing both sides by 3, we obtain
y=7/3
Let us evaluate both the LHS and RHS for validate the answer
NCERT Solutions for Linear equations Class 8 Mathematics Chapter 2
L.H.S. = R.H.S.
It proves that result is correct
Question 10
 Solve and check result:
NCERT Solutions for Linear equations Class 8 Mathematics Chapter 2
Answer
NCERT Solutions for Linear equations Class 8 Mathematics Chapter 2
Transposing 3m to R.H.S and 8/5 to L.H.S
8/5= 2m
Dividing both sides by 2
m=4/5
Let us evaluate both the LHS and RHS for validate the answer
L.H.S =  3m=12/5
R.H.S = 5m –(8/5)=12/5
L.H.S. = R.H.S.
It proves that result is correct

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