If (x - y) = 12^(1/2) and (x + y) = 3^(1/2), what is the value of x^2

Question

If  (x - y) =\sqrt{12}  and  (x + y) = \sqrt{3} , what is the value of  x^2 - y^2 ?

(A) 3
(B) 6
(C) 9
(D) 36
(E) It cannot be determined from the information given.

KSBGC · Answer

Given

(x - y) =\sqrt{12}

(x + y) = \sqrt{3}

x^2 - y^2

= (x+y) (x-y)

=  \sqrt{12}   \sqrt{3}

=  \sqrt{36}

= 6

The best answer is B.

sudarshan22 · Answer

+ for   B

= x^2 - y^2
= (x + y) * (x - y)
= √3 * √12
= √36
= 6

Hence,   B  .

EgmatQuantExpert · Answer

Solution

Given:

•  (x−y)= \sqrt{12} 
•  (x+y)=\sqrt{3}

To find:  
• The value of  x^2- y^2 .

Approach and Working:

•  x^2- y^2= (x-y)(x+y) 
• = \sqrt{12}*\sqrt{3}= \sqrt{36}= 6

Hence, the correct answer is option B.

Answer: B

MrJglass · Answer

√12 * √3 = √12(3) = √36 = 6.

Next?

Abhishek009 · Answer

x^2 - y^2 = (x - y)(x + y)

So,  x^2 - y^2 = \sqrt{12}*\sqrt{3}

Or,  x^2 - y^2 = \sqrt{36}

Thus,  x^2 - y^2 = 6 , Answer must be (B)

ScottTargetTestPrep · Answer

Let’s first factor the expression x^2 - y^2 and then substitute with the given values:

x^2 - y^2 = (x - y)(x + y) = (√12)(√3) = √36 = 6

Answer: B

Kinshook · Answer

Asked: If  (x - y) =\sqrt{12}  and  (x + y) = \sqrt{3} , what is the value of  x^2 - y^2 ?

x^2 - y^2 = (x+y)(x-y) = \sqrt{3}*\sqrt{12} = \sqrt{36} = 6

IMO B

If (x - y) = 12^(1/2) and (x + y) = 3^(1/2), what is the value of x^2

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GMAT Problem Solving (PS) Questions

If (x - y) = 12^(1/2) and (x + y) = 3^(1/2), what is the value of x^2

Prep Toolkit

615 to 715 in 15 Days (Ria's Strategies)

More than Quant/Verbal Abilities: Speed vs. Accuracy

745 with Only Self-Prep and GMAT Club

From 555 to 765: 210-point Improvement

Perfect 805 Score Debrief by Julia

My Rewards