Question

Using quadratic formula, solve for x.
9x2 - 3(a + b)x + ab =0
2
​

Answer 1

Answer:

Step-by-step explanation:⇒ Here, a=9,b=−3(a+b),c=ab

⇒ x=

2a

−b±

b

2

−4ac

​

​

=

2(9)

−[−3(a+b)]±

[−3(a+b)]

2

−4(9)(ab)

​

​

=

18

3a+3b±

9(a

2

+b

2

+2ab)−36ab

​

​

=

18

3a+3b±

9a

2

+9b

2

+18ab−36ab

​

​

=

18

3a+3b±

9a

2

+9b

2

−18ab

​

​

18

3a+3b±

9(a

2

+b

2

−2ab)

​

​

=

18

3a+3b±

9(a−b)

2

​

​

=

18

3a+3b±3(a−b)

​

=

18

3a+3b±3a−3b

​

x=

18

3a+3b+3a−3b

​

and x=

18

3a+3b−3a+3b

​

x=

18

6a

​

and x=

18

6b

​

∴ x=

3

a

​

,

3

b

​