Question

x²-(a+b)x+6=O then find its others root

Answer 1

Given quadratic equation, x

2

+(3−2a)x−6a=0

Now, putting x=−3

we have (−3)

2

+(3−2a)(−3)−6a=0

9−9+6a−6a=0

0=0

since, x=−3 satisfies the given equation -3 is one of the root of the quadratic equation.

x

2

+(3−2a)x−6a=0

x

2

+3x−2ax−6a=0

x(x+3)−2a(x+3)=0

(x−2a)(x+3)=0

So, x−2a=0 or x+3=0

x=2a or x=−3

Hence, the other root is 2a.