NCERT Class 8 Maths Chapter 2 Linear Equations in One Variable Exercise 2.3

Chapter 2 Linear Equations in One Variable Exercise 2.3

Solve the following equations and check your results.
Question 1: 3x = 2x + 18
Answer:
= 3x = 2x + 18
= 3x - 2x = 18
= x = 18

Question 2: 5t - 3 = 3t - 5
Answer:
= 5t - 3 = 3t - 5
= 5t - 3t = -5 + 3
= 2t = -2
= t = -1

Question 3: 5x + 9 = 5 + 3x
Answer:
= 5x + 9 = 5 + 3x
= 5x - 3x = 5 - 9
= 2x = -4
= x = -2

Question 4: 4z + 3 = 6 + 2z
Answer:
= 4z + 3 = 6 + 2z
= 4z - 2z = 6 - 3
= 2z = 3
= z = 3/2

Question 5: 2x - 1 = 14 - x
Answer:
= 2x - 1 = 14 - x
= 2x + x = 14 + 1
= 3x = 15
= x = 5

Question 6: 8x + 4 = 3(x - 1) + 7
Answer:
= 8x + 4 = 3(x - 1) + 7
= 8x + 4 = 3x - 3 + 7
= 8x - 3x = -3 + 7 - 4
= 5x = 0
= x = 0/5
= x = 0

Question 7: x = 4/5 (x + 10)
Answer:
= x = 4/5 (x + 10)
= 5x = 4x + 40
= 5x - 4x = 40
= x = 40

Question 8: 2x/3 + 1 = 7x/15 + 3
Answer:
= 2x/3 + 1 = 7x/15 + 3
= 2x/3 - 7x/15 = 3 - 1
= 3x/15 = 2
= 1x/5 = 2
= x = 2 × 5
= x = 10

Question 9: 2y + 5/3 = 26/3 - y
Answer:
= 2y + 5/3 = 26/3 - y
= 2y + y = 26/3 - 5/3
= 3y = 21/3
= 3y = 7
= y = 7/3

Question 10: 3m = 5m - 8/5
Answer:
= 3m = 5m - 8/5
= 3m - 5m = -8/5
= -2m = -8/5
= 2m = 8/5
= m = 8/5 ÷ 2/1
= m = 8/5 × 1/2
= m = 8/10
= m = 4/5