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If the positive difference of the square roots of two integers is \(\sqrt{15 - 10\sqrt{2}}\), what is the square of the difference between these two integers?

\(\sqrt{a} - \sqrt{b} = \sqrt{15 - 10\sqrt{2}}\)

(a-b)^2 = ?

\(\sqrt{a} - \sqrt{b} = \sqrt{15 - 10\sqrt{2}}\)
taking square on both sides

\( a + b - 2\sqrt{ab} = 15 - 10\sqrt{2}\)

a + b = 15
ab = 50
Case 1: a = 10; b= 5
Case 2: a = 5; b = 10

(a - b)^2 = (10-5)^2 = 5^2 = 25

IMO C
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x^1/2-y^1/2 = (15-(10^1/2))^1/2 and we need to find (x-y)^2
sq. both sides

x+y-2(xy)^1/2 = 15-(10^1/2)
x+y=15 and -2(xy)^1/2=-10(2)^1/2
solving the 2 equations will give x as 10 and 5 and y as 5 and 10 respectively.

(x-y)^2 = (10-5)^2 = 25
Bunuel
If the positive difference of the square roots of two integers is \(\sqrt{15 - 10\sqrt{2}}\), what is the square of the difference between these two integers?

A. 9
B. 16
C. 25
D. 100
E. 225


 


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Bunuel
If the positive difference of the square roots of two integers is \(\sqrt{15 - 10\sqrt{2}}\), what is the square of the difference between these two integers?

A. 9
B. 16
C. 25
D. 100
E. 225


 


This question was provided by GMAT Club
for the GMAT Club Olympics Competition

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We have \(\sqrt{a} - \sqrt{b} = \sqrt{15 - 10\sqrt{2}}\)
=> \((\sqrt{a} - \sqrt{b})^2 = (\sqrt{15 - 10\sqrt{2}})^2\)
=>\( a - 2\sqrt{a}\sqrt{b} + b = 15 - 10\sqrt{2}\)
We can see matching both side: a + b = 15 and \(-2\sqrt{a}\sqrt{b} = -10\sqrt{2} = -2*\sqrt{50}\)
=> a = 10 and b = 5
=> The square of the difference between 2 integers : \( (a - b)^2 = (10 - 5)^2 =25 \)

Answer: C.25
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\(\sqrt{a} - \sqrt{b} = \sqrt{15 - 10[square_root]2}[/square_root]\)
\(a + b - 2\sqrt{ab} = 15 - 10\sqrt{2}\)
we can infer that a = 10, b = 5.
(a-b)^2 = 5^2 = 25

Answer: C
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Given Equation: \(\sqrt{15-10 \sqrt{2}}\)

Let the two integers be x and y, such that x>y
Find: \((x-y)^2\)

\(\sqrt{x}-\sqrt{y} = \sqrt{15-10\sqrt{2}}\)
Squaring both sides
\((\sqrt{x}-\sqrt{y})^2 = 15-10\sqrt{2}\)
\(x+y -2(\sqrt{x})(\sqrt{y}) = 15-2*5\sqrt{2}\)
\(x+y -2(\sqrt{x})(\sqrt{y}) = 15-2\sqrt{2*25}\)

From above, we can get:
\(x+y = 15\)
\(2(\sqrt{x})(\sqrt{y}) = 2\sqrt{50}\)
Factors of 50 that equal 15: 10*5
Therefore, x=10, y=5

\((x-y)^2 = (10-5)^2\)

\(= (5)^2 = 25\)

Answer choice C. 25 is right.
Bunuel
If the positive difference of the square roots of two integers is \(\sqrt{15 - 10\sqrt{2}}\), what is the square of the difference between these two integers?

A. 9
B. 16
C. 25
D. 100
E. 225


 


This question was provided by GMAT Club
for the GMAT Club Olympics Competition

Win over $30,000 in prizes such as Courses, Tests, Private Tutoring, and more

 

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Bunuel
If the positive difference of the square roots of two integers is \(\sqrt{15 - 10\sqrt{2}}\), what is the square of the difference between these two integers?

A. 9
B. 16
C. 25
D. 100
E. 225


 


This question was provided by GMAT Club
for the GMAT Club Olympics Competition

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Let the two integers be a,b.

Then, the square root of two integers are \sqrt{ a }, \sqrt{ b }.

sqrt (a) - sqrt (b) = sqrt [ 15 - 10* sqrt (2) ]

squaring on both sides, we get

a + b - 2*a*b = 15 - 10* sqrt (2)

comapring, we get

a + b = 15

2 *a*b = 10 * sqrt (2) . Hence, a*b = sqrt (25*2) = sqrt (50).

a*b = 50

Thus, a = 10, b = 5.

Difference = (10-5) = 5.

Square of the difference = 5^2 = 25

Option C
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|sqr(X) - Sqr(y)| = sqr( 15 - 10sqr(2) )

(sqr(X) - Sqr(y) )^2 = 15 - 10sqr(2)
x+y - 2sqr(x)sqr(y) = 15 - 10sqr(2)

looking at the equation structure
x+y = 15, and 2sqr(x)sqr(y) = 10sqr(2)

sqr(x)sqr(y) = 5sqr(2)
sqr(x)sqr(y) = sqr(50) and x+y = 15
X = 10 and y = 5

Difference = 5 or -5


Square of the difference = 25
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My Answer is C 25

Let take first number be x and another be y

As pet the question\sqrt{ x}-\sqrt{y}=\(\sqrt{15 - 10\sqrt{2}}\)

On squaring both sides, we will get x+y-2\sqrt{xy}=15-10\sqrt{2}

Now on comparing we can say x+y=15 and

2\sqrt{xy}=0\sqrt{2} on simplification by squaring both sides we will get xy=50

Now since it is given that difference is positive so we can say x>y so we need number whose sum is 15 and product is 50 we can say x can be 10 and y can be 5

So the answer(10-5) to the power 2 so answer will be 25 which is C


Bunuel
If the positive difference of the square roots of two integers is \(\sqrt{15 - 10\sqrt{2}}\), what is the square of the difference between these two integers?

A. 9
B. 16
C. 25
D. 100
E. 225


 


This question was provided by GMAT Club
for the GMAT Club Olympics Competition

Win over $30,000 in prizes such as Courses, Tests, Private Tutoring, and more

 

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If the positive difference of the square roots of two integers is √(15 - 10√2)
, what is the square of the difference between these two integers?

Take X and Y as the two integers.

√(x) - √(y) = √(15 - 10√2)

take the square of both sides

x - y = 15 - 10√2

take the square of both sides again

x2 - y2 = 225 - 102 x 2 = 25

Answer C

√(15 - 10√2)
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\(\sqrt{x}-\sqrt{y}=\sqrt{15-10\sqrt{2}}\)

Squaring both sides; \(x+y-2\sqrt{xy}=15-10\sqrt{2}\)

\(x+y=15\) & \(2\sqrt{xy}=10\sqrt{2}=2*5*\sqrt{2}=2\sqrt{50}\)

\(xy=50\)

These are sum & product of a quadratic equation

\(k^2-15k+50=0\)

\(x=10\) & \(y=5\)

\(x-y=10-5=5\)

\((x-y)^2=25\)

Answer: C
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We assign a and b for the numbers. Based on the question: \(\sqrt{a}-\sqrt{b}= \sqrt{15 - 10\sqrt{2}} \)
Then, if we square both sides: \(a+b-2\sqrt{ab}=15-10\sqrt{2}\)
We know that we can write \(10\sqrt{2}\) as \(2\sqrt{50}\), so it resembles the left side of the equation. Then we'll have:
\(a+b-2\sqrt{ab}=15-2\sqrt{50}\)
From this, we know \(a+b=15\) and \(ab=50\)
We can easily see that 10 and 5 could be an answer to this equation.
The question asks for \((a-b)^2\). If we put 10 and 5, then \((a-b)^2=25\), which is in the answer choices.

The answer is C.
Bunuel
If the positive difference of the square roots of two integers is \(\sqrt{15 - 10\sqrt{2}}\), what is the square of the difference between these two integers?

A. 9
B. 16
C. 25
D. 100
E. 225


 


This question was provided by GMAT Club
for the GMAT Club Olympics Competition

Win over $30,000 in prizes such as Courses, Tests, Private Tutoring, and more

 

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let two numbers be g-greater s-smaller
{ here a^1/2=square root(a)}where a is any no.
as per condition ( g^1/2) - (s^1/2)=(15-10*2^1/2)^1/2
squaring both sides (g+s) - 2*(gs)^1/2=15-10*2^1/2
=>g+s - 2(gs)^1/2 = 15 -2*50^1/2
on comparing left and right hand sides; g+s=15 & g*s=50
so g=10 and s=5 satisfies above
hence (g-s)^2=25
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sqrt = square root

sqrt( x ) - sqrt(y) = sqrt( 15 - 10*(sqrt(2)) )

( sqrt( x ) - sqrt(y) ) ^ 2 = ( ( 15 - 10*(sqrt(2)) )^(1/2) ) ^2 )

x + y - 2*( sqrt(x * y ) ) = 15 - 10*sqrt(2)

x + y = 15 (i)

- 2*( sqrt(x * y ) ) = - 10*sqrt(2)
( sqrt(x * y ) ) = 5*sqrt(2)
( sqrt(x * y ) ) = sqrt( 50 )

x*y = 50 (ii)

Now, with this two equations:
x = 10 and y = 5 OR x = 5 and y = 10

Difference between X and Y = 5
Square of difference = 5^2 = 25

Answer = C. 25
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Bunuel
If the positive difference of the square roots of two integers is \(\sqrt{15 - 10\sqrt{2}}\), what is the square of the difference between these two integers?

A. 9
B. 16
C. 25
D. 100
E. 225


 


This question was provided by GMAT Club
for the GMAT Club Olympics Competition

Win over $30,000 in prizes such as Courses, Tests, Private Tutoring, and more

 


\(|\sqrt{x} - \sqrt{y}| = \sqrt{15 - 10\sqrt{2}}\)

Squaring both sides we get

\(x + y - 2\sqrt{xy} = 15 - 10\sqrt{2}\)

\(\sqrt{xy} = 5\sqrt{2}\)

Squaring both sides

xy = 50

x = 50/y

x + y = 15

y + 50/y = 15

y^2 -15y +50 = 0

y = 10 or y = 5

x = 5 or x = 10

y - x = 5

Square = 25

Option C
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If the positive difference of the square roots of two integers is \(sqrt(15−10√2)\), what is the square of the difference between these two integers?

ATP, sqrt(a-b) = sqrt(15−10√2)

for this to be true, a has to be = 15 and b = 10√2.

so, we have been asked for \(a^2 - b^2.\)

\(a^2 - b^2 = 15^2 - (10√2)^2 \)

\(=> a^2 - b^2 = 225 - 200 = 25\)

Option C.
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Given data,

the positive difference of the square roots of two integers = √(15−10√2)

i.e., √a-√b = √(15−10√2)

apply squaring on both sides

a+b +2√(ab) = 15 -10√2

we can observe, a+b = 15 and

2√(ab) = 10√2 => cancel 2 and apply square on both sides => ab = 25(2) = 50

the square of the difference between these two integers = ?

a^2 - b^2 = ?

we know that, a^2 -b^2 = (a+b)^2 - 4ab

substitute a+b = 15 and ab = 50

= (15)^2 - 4(50)
= 225 -200
= 25

Therfore, answer is 25
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We are given:
(15 − 10 * 2^0.5)^0.5 = (a^0.5 − b^0.5)
Square both sides
-> (15 − 10 * 2^0.5) = a + b - 2 (ab)^0.5
-> 10 + 5 − 2 * (10 * 5)^0.5 = a + b - 2 (ab)^0.5
So, a = 10, b = 5

Difference = 10 − 5 = 5
Square of diff = 5^2 = 25

Answer: C
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