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555-605 (Medium)|   Algebra|      
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Bunuel
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If x and y are positive numbers, √x + √y = 6 and xy = 4, then what is 09 Mar 2020, 02:27
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C
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35% (medium)

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70% (01:20) correct 30% (01:53) wrong based on 162 sessions

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Competition Mode Question



If x and y are positive numbers, \(√x + √y = 6\) and \(xy = 4\), then what is the value of \(x + y\) ?

A. 2
B. 28
C. 32
D. 34
E. 36



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C
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If x and y are positive numbers, √x + √y = 6 and xy = 4, then what is 09 Mar 2020, 02:59
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If x and y are positive numbers, \(√x + √y = 6\) and \(xy = 4\), then what is the value of \(x + y\) ?


Square the equation
\((\sqrt{x}+\sqrt{y})^2=6^2.......x+y+2\sqrt{xy}=36.....x+y+2\sqrt{4}=36.....x+y=36-4=32\)

C
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If x and y are positive numbers, √x + √y = 6 and xy = 4, then what is 09 Mar 2020, 07:04
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consider sqrt(x)+sqrt(y)=6
square on both sides,we get
x+y+2*sqrt(x*y)=36
given x*y=4
x+y+2*2=36
x+y=32
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If x and y are positive numbers, √x + √y = 6 and xy = 4, then what is 09 Mar 2020, 07:39
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If \(x \) and \(y\) are positive numbers, \(√x+√y=6\) and \(xy=4\), then what is the value of \(x+y\) ?

\(√x+√y=6\)
Square the both sides: \((√x+√y)^{2}=6^{2}\)
--> \(x+ y +2√(xy) = 36 \)

\(x+ y = 36 -2√(xy) = 36 -2√4= 36-4= 32\)

The answer is C.
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If x and y are positive numbers, √x + √y = 6 and xy = 4, then what is Updated on: 10 Mar 2020, 07:32
Originally posted by Archit3110 on 09 Mar 2020, 08:22.
Last edited by Archit3110 on 10 Mar 2020, 07:32, edited 1 time in total.
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√x+√y=6
xy=4
square both sides
√x+√y=6
x+y+2√xy=36
x+y+2√4= 36
x+y+4=36
x+y=32
IMO C

If x and y are positive numbers, √x+√y=6 andxy=4, then what is the value of x+y ?

A. 2
B. 28
C. 32
D. 34
E. 36
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If x and y are positive numbers, √x + √y = 6 and xy = 4, then what is 09 Mar 2020, 10:41
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If x and y are positive numbers, √x+√y=6 and xy=4, then what is the value of x+y ?

A. 2
B. 28
C. 32
D. 34
E. 36

\((√x+√y)^2 = 6^2 \)
x + y + 2√x√y = 36
x + y = 36 - 2.√4
x + y = 36 - 4 = 32

Answer C.
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If x and y are positive numbers, √x + √y = 6 and xy = 4, then what is 09 Mar 2020, 11:56
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If x and y are positive numbers, √x+√y=6√x+√y=6 and xy=4xy=4, then what is the value of x+yx+y ?

A. 2
B. 28
C. 32
D. 34
E. 36

x + 2\sqrt{xy}+ y = 36
x + 2. 2 (for square root, we consider only the positive value) +y = 36
x + y = 32.

C is the answer
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If x and y are positive numbers, √x + √y = 6 and xy = 4, then what is 09 Mar 2020, 13:36
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(√x + √y)^2 = 36
x+2\(\sqrt{xy}\)+y = 36

substitute in xy = 4

x+ y + 4 = 36
x + y = 32

Answer: C
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If x and y are positive numbers, √x + √y = 6 and xy = 4, then what is Updated on: 10 Mar 2020, 08:36
Originally posted by exc4libur on 09 Mar 2020, 17:38.
Last edited by exc4libur on 10 Mar 2020, 08:36, edited 1 time in total.
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Quote:
If x and y are positive numbers, √x+√y=6 and xy=4, then what is the value of x+y?

A. 2
B. 28
C. 32
D. 34
E. 36
Show more

√x+√y=6
(√x+√y)^2=6^2
x+y+2√xy=36
x+y=36-2(√4)
x+y=36-4=32

Ans (C)
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If x and y are positive numbers, √x + √y = 6 and xy = 4, then what is 09 Mar 2020, 21:12
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x + y = (√x+√y)^2 - 2√(xy) = 36 - 2√4 = 36 - 4 = 32

ANSWER IS (C)
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If x and y are positive numbers, √x + √y = 6 and xy = 4, then what is 09 Mar 2020, 21:52
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If x and y are positive numbers, √x+√y=6 and xy=4, then what is the value of x+y ?

A. 2
B. 28
C. 32
D. 34
E. 36

Given that,
√x+√y=6
(√x+√y)^2=6^2 ( Squaring to the both sides)
Or, x + 2√xy+ y = 36
Or, x + y + 2√xy = 36
Or, x + y + 2*2 = 36( Putting xy =4)
Or, x + y = 32

Answer: C(32)
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If x and y are positive numbers, √x + √y = 6 and xy = 4, then what is 04 Jul 2024, 05:28
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