Which method is the most efficent method to use to solve x^2-11=0?
factoring

isolating the x^2 term and finding the square root of both sides

using the quadratic formula

all three methods would be efficent

Question

Which method is the most efficent method to use to solve x^2-11=0?
factoring

isolating the x^2 term and finding the square root of both sides

using the quadratic formula

all three methods would be efficent

umerlodhi · Answer

@ganeshie8 @TheSmartOne

umerlodhi · Answer

@jabez177 @sleepyjess

sleepyjess · Answer

What do you think? Which option will be quickest and easiest?

umerlodhi · Answer

no wait i think its B

sleepyjess · Answer

That's not what I was thinking, the quadratic formula takes some time to work out

sleepyjess · Answer

Yep :)

umerlodhi · Answer

thanks so much!!

sleepyjess · Answer

No problem ^_^

thesmartone · Answer

IMO, I think the answer is D

Factoring it using:
a^2 - b^2 = (a + b)(a - b)

Using the quadratic formula

or isolating x^2
x^2 = 11
x = plus or minus sqrt(11)

sleepyjess · Answer

@TheSmartOne , this equation is impossible to solve by factoring though

sleepyjess · Answer

It also says the MOST efficient, I wouldn't consider the quadratic formula to be "efficient" for this equation

thesmartone · Answer

I guess that's what they want you to say :P

factoring for this question is efficient if they teach kids a^2 - b^2 = (a + b)(a - b)

sleepyjess · Answer

but 11 is prime, it can't be factored

thesmartone · Answer

$\Large (\sqrt{11})^2 = 11$

sleepyjess · Answer

using $\sqrt{11}$ isn't exactly ideal for factoring....

thesmartone · Answer

The correct answer is actually D

I helped someone with it and they got D as the correct answer

umerlodhi · Answer

oh snap i submitted it yesterday and got 4/5 idk which one was wrong and now the quiz is locked so i cant check