RS Aggarwal V Aggarwal
Class 9th math chapter 3 Exercise 3A solution
Factorise
1. 9x²+12xy
Solution: Given 9x²+12xy
=3x(3x+4y)
2. 18x²-24xyz
Solution: Given 18x²-24xyz
= 6x(3x-4yz)
3. 27a³b³-45a⁴b²
Solution: Given 27a³b³-45a⁴b²
=9×3×a³b²×b-9×5×a³b²×a
=9a³b²×3b-9a³b²×5a
= 9a³b²(3b-5a)
4. 2a(x+y)-3b(x+y)
Solution: Given 2a(x+y)-3b(x+y)
= (x+y)(2a-3b)
5. 2x(p²+q²)+4y(p²+q²)
Solution: Given 2x(p²+q²)+4y(p²+q²)
=2×x×(p²+q²)+2×2×y×(p²+q²)
= 2×(p²+q²)(2x+4y)
6. x(a-5)+y(5-a)
Solution: Given x(a-5)+y(5-a)
= x(a-5)+y(-a+5)
= x(a-5)+y{-(a-5)}
= x(a-5)-y(a-5)
= (a-5)(x-y)
7. 4(a+b)-6(a+b)²
Solution: Given 4(a+b)-6(a+b)²
=2×2(a+b)-2×3×(a+b)²
=2(a+b)[2-3(a+b)]
=2(a+b)(2-3a-3b)
