Need the solution to the below problem

Multiply both sides by

1/√5

Shouldn’t there be √5 +1= a/√5 +b ???

\frac{20}{5 - \sqrt{5}}*\frac{5 + \sqrt{5}}{5 + \sqrt{5}} = \frac{100 + 20\sqrt{5}}{25 - 5} = \frac{100 + 20\sqrt{5}}{20} = 5 + \sqrt{5}

Now, compare (5 + \sqrt{5}) to (a + b\sqrt{5})

a = 5

b = 1

a+b = 5+1 = 6

Ans. B

Thanks a lot!

No

You are multiplying \frac{1}{\sqrt{5}} to only one of the terms

(a+b\sqrt{5}) * \frac{1}{\sqrt{5}} is going to give (\frac{a}{\sqrt{5}}+b)

Is it allowed to multiply only one term during Quantitative comparison?

Who knows , Is there a solution to this problem ?

Yes

I mean the video solution?

No, there isn’t at the moment

I think until Greg clears it people should follow your solution , I think I just got lucky

What you did was

while what you really intended to do was

Ahh , I see

Exactly