Factorisation

28. The factors of x² – 4 are

• (A) (x – 2), (x – 2)
• (B) (x + 2), (x – 2)
• (C) (x + 2), (x + 2)
• (D) (x – 4), (x – 4)

27. Which of the following is not the correct value of –20x⁴ ÷ 10x²?

• (A) –x² – x²
• (B) –2x²
• (C) –2x × x
• (D) –2x

26. Which of the following is the correct value of (2x)²?

• (A) 2x²
• (B) 4x²
• (C) 4x
• (D) x²

25. Factorisation of 5z² – 80 is

• (A) 5(z² – 16)
• (B) 5(z – 16)
• (C) 5(z – 4)(z + 4)
• (D) (z – 4)(z + 4)

24. The value of (–27x²y) ÷ (–9xy) is

• (A) 3xy
• (B) –3xy
• (C) –3x
• (D) 3x

23. The value of (2x² + 4) ÷ 2 is

• (A) 2x² + 2
• (B) x² + 2
• (C) x² + 4
• (D) 2x² + 4

22. Which of the following is the correct value of 3(x – 4)?

• (A) 3x – 4
• (B) 3x – 12
• (C) x – 4
• (D) x – 12

21. Which of the following is the correct value of (x + 8)²?

• (A) x² + 64
• (B) x² + x + 64
• (C) x² + 16x
• (D) x² + 16x + 64

20. Which of the following is the correct value of (x – 5)²?

• (A) x² – 25
• (B) x² – x + 25
• (C) x² – 10x + 25
• (D) x² – 10x + 5

19. Which of the following is the correct value of 2x + 3y?

• (A) 6xy
• (B) 5x + y
• (C) 2x + 3y
• (D) 5xy

18. Factorised form of 18mn + 10mnp is

• (A) 18m(n + np)
• (B) 2mn(9 + 5p)
• (C) 2mn(9 + 10p)  
• (D) 10mn(1 + p)

17. Factorised form of 4y² – 12y + 9 is

• (A) (2y – 3)(2y + 3)
• (B) (2y – 3)(2y – 3)
• (C) (y – 3)(2y – 3)  
• (D) (y – 3)(y – 3)

16. 38x³y²z ÷ 19xy² is equal to

• (A) 2x²z
• (B) 2xyz
• (C) 2x²y
• (D) 2xy

15. Simplified value of (9x – 81) ÷ 9 is

• (A) x – 9
• (B) x – 81
• (C) x + 81
• (D) x + 9