Question #4...
If xy ≠ 0, what is the value of 25x^2/y^2
(1) x = 3
(2) 5x – 2y = 0
( A ) Statement (1) ALONE is sufficient, but statement (2) alone is not sufficient.
( B ) Statement (2) ALONE is sufficient, but statement (1) alone is not sufficient.
( C ) BOTH statements TOGETHER are sufficient, but NEITHER statement ALONE is sufficient.
( D ) EACH statement ALONE is sufficient.
( E ) Statements (1) and (2) TOGETHER are NOT sufficient.
OA b
Why is 1 insufficient - can't we plug in the value of x and find Y?
If xy ≠ 0 ..... Please help
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I'd start off by simplifying 25x^2 / y^2 into: (5^2)(x^2) / (y^2)
You can then take the square root of the expression above, leaving you with: 5x / y
Then, we can rephrase the question as: "What's 5x/y equal to?"
Stem #1 only gives the value for x, but we need both x and y to solve the question.
Stem #2, when simplified, gives us the answer:
5x - 2y = 0
5x = 2y
5x/y = 2
Therefore, the answer is B
You can then take the square root of the expression above, leaving you with: 5x / y
Then, we can rephrase the question as: "What's 5x/y equal to?"
Stem #1 only gives the value for x, but we need both x and y to solve the question.
Stem #2, when simplified, gives us the answer:
5x - 2y = 0
5x = 2y
5x/y = 2
Therefore, the answer is B
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@ moonlinght - if you plug in teh values and solve, you shall arrive with answer C. However, read the question statement for choice C
"( C ) BOTH statements TOGETHER are sufficient, but NEITHER statement ALONE is sufficient. "
In this case, B along is sufficient, hence C is wrong
"( C ) BOTH statements TOGETHER are sufficient, but NEITHER statement ALONE is sufficient. "
In this case, B along is sufficient, hence C is wrong