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ncert solutions for class 8 maths chapter 12 exercise 12.4

In this page we have ncert solutions for class 8 maths chapter 12 exercise 12.4 for Factorisation.This exercise has questions about common mistakes/error done while doing factorisation Hope you like them and do not forget to like , social share and comment at the end of the page.

NCERT solutions for class 8 maths chapter 12 ex 12.4

Question 1
Find and correct the errors in the statement: 4(x - 5) = 4x - 5
Answer
LHS =4(x-5) = 4x-20
RHS = (4x-5)
LHS≠ RHS
Correct statement would be
4(x-5) = 4x-20

Question 2
Find and correct the errors in the statement: x(3x + 2) = 3x² + 2
Answer
LHS = x(3x + 2) = 3x² + 2x
RHS = 3x² + 2
LHS≠ RHS
Correct statement would be
x(3x + 2) = 3x² + 2x

Question 3
Find and correct the errors in the statement: 2x + 3y = 5xy
Answer
LHS = 2x + 3y
RHS = 5xy
LHS≠ RHS
Correct statement would be
2x + 3y = 2x+3y

Question 4
Find and correct the errors in the statement: x + 2x + 3x = 5x
Answer
LHS = x + 2x + 3x= 6x
RHS = 5x
LHS≠ RHS
Correct statement would be
x + 2x + 3x= 6x

Question 5
Find and correct the errors in the statement: 5y + 2y + y - 7y = 0
Answer
LHS = 5y + 2y + y - 7y = y
RHS = 0
LHS≠ RHS
Correct statement would be
5y + 2y + y - 7y = y

Question 6
Find and correct the errors in the statement: 3x + 2x = 5x²
Answer
LHS = 3x + 2x =5x
RHS = 5x²
LHS≠ RHS
Correct statement would be
3x + 2x =5x

Question 7
Find and correct the errors in the statement: (2x)² + 4(2x) + 7 = 2x² + 8x + 7
Answer
LHS = (2x)² + 4(2x) + 7 =4x² +8x+7
RHS = 2x² + 8x + 7
LHS≠ RHS
Correct statement would be
(2x)² + 4(2x) + 7 =4x² +8x+7

Question 8
Find and correct the errors in the statement: (2x)² + 5x = 4x + 5x = 9x
Answer
LHS = (2x)² + 5x =4x²+5x
RHS = 4x + 5x =9x
Third = 9x
LHS≠ RHS =third part
Correct statement would be
(2x)² + 5x = 4x²+5x

Question 9
Find and correct the errors in the statement: (3x + 2)² = 3x² + 6x + 4
Answer
LHS = (3x + 2)² =9x² +12x+4
RHS = 3x² + 6x + 4
LHS≠ RHS
Correct statement would be
(3x + 2)² =9x² +12x+4

Question 10
Find and correct the errors in the statement: (y - 3)² = y² - 9
Answer
LHS = (y - 3)² =y² -6y+9
RHS = y² - 9
LHS≠ RHS
Correct statement would be
(y - 3)² =y² -6y+9

Question 11
Find and correct the errors in the statement: (z + 5)² = z² + 25
Answer
LHS= (z + 5)² =z² +10z+25
RHS = z² + 25
LHS≠ RHS
Correct statement would be
(z + 5)² =z² +10z+25

Question 12
Find and correct the errors in the statement: (2a + 3b) (a - b) = 2a² - 3b²
Answer
LHS= (2a + 3b) (a - b)=2a² -2ab+3ab-3b²=2a² +ab-3b²
RHS = 2a² - 3b²
LHS≠ RHS
Correct statement would be
(2a + 3b) (a - b)=2a² +ab-3b²

Question 13
Find and correct the errors in the statement: (a + 4) (a + 2) = a² + 8
Answer
LHS= (a + 4) (a + 2) =a² +2a+4a+8=a² +6a+8
RHS = a² + 8
LHS≠ RHS
Correct statement would be
(a + 4) (a + 2) =a² +6a+8

Question 14
Find and correct the errors in the statement: (a - 4) (a - 2) = a² - 8
Answer
LHS= (a - 4) (a - 2) =a² -2a-4a+8=a² -6a+8
RHS = a² - 8
LHS≠ RHS
Correct statement would be
(a - 4) (a - 2) =a² -6a+8

Question 15
Find and correct the errors in the statement: 3x²/3x² =0
Answer
LHS= 3x²/3x² =1
RHS =0
LHS≠ RHS
Correct statement would be
3x²/3x² =1

Question 16
Find and correct the errors in the statement: (3x²+1)/3x² = 1+1=2
Answer
LHS= (3x²+1)/3x² = 1 + 1/3x²
RHS =1+1
LHS≠ RHS
Correct statement would be
(3x²+1)/3x² = 1 + 1/3x²

Question17
Find and correct the errors in the statement: 3x/(3x+2) = 1/2
Answer
LHS= 3x/(3x+2)
RHS =1/2
LHS≠ RHS
Correct statement would be
3x/(3x+2) =3x/(3x+2)

Question 18
Find and correct the errors in the statement:
3/(4x+3) =1/4x
Answer
LHS= 3/(4x+3)
RHS =1/4x
LHS≠ RHS
Correct statement would be
3/(4x+3) =3/(4x+3)

Question 19
Find and correct the errors in the statement:
(4x+5)/4x =5
Answer
LHS= (4x+5)/4x =1 + 5/4x
RHS =5
LHS≠ RHS
Correct statement would be
(4x+5)/4x =1 + 5/4x

Question 20
Find and correct the errors in the statement: (7x+5)/5 =7x
Answer
LHS= (7x+5)/5 = 7x/5 +1
RHS =7x
LHS≠ RHS
Correct statement would be
(7x+5)/5 = 7x/5 +1

Summary

NCERT solutions for class 8 maths chapter 12 Exercise 12.1 has been prepared by Expert with utmost care. If you find any mistake.Please do provide feedback on mail. You can download the solutions as PDF in the below Link also
Download class8 maths Exercise 12.4 as pdf
This chapter 12 has total 3 Exercise 12.1,12.2,13.3 as per latest syllabus. Exercise 12.4 is the deleted exercise. This is the deleted exercise in the chapter.You can explore previous exercise of this chapter by clicking the link below

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