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If x and y are the lengths of the legs of a right triangle, what is th
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26 Apr 2019, 02:13
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If x and y are the lengths of the legs of a right triangle, what is the value of xy ? (1) The hypotenuse of the triangle is \(10\sqrt{2}\). (2) The area of the triangular region is 50. DS94602.01 OG2020 NEW QUESTION
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If x and y are the lengths of the legs of a right triangle, what is th
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Updated on: 11 May 2019, 08:53
The Logical approach to this question will start by pointing out that since the area of a right triangle is half the product of its legs, then xy is twice the triangle's area. Statement (1) gives us just the hypotenuse. Since the pythagorean theorem is an equation with three variables we must know the value of two of the three in order to solve it (i.e. x² + y² = 200 wouldn't give us the value of x or the value of y). Statement (2) is just what we were looking for: xy, as mentioned above, is half the triangular area. The correct answer is (B). Posted from my mobile device
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Re: If x and y are the lengths of the legs of a right triangle, what is th
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27 Apr 2019, 22:18
DavidTutorexamPAL wrote: The Logical approach to this question will start by pointing out that since the area of a right triangle is half the product of its legs, then xy is twice the triangle's area. Statement (1) gives us just the hypotenuse. Since the pythagorean theorem is an equation with three variables we must know the value of two of the three in order to solve it (i.e. x² + y² = 200 wouldn't give us neither x not y). Statement (2) is just what we were looking for: xy, as mentioned above, is half the triangular area. The correct answer is (B).
Posted from my mobile device legs of a right angle triangle = two sides other than the Hypo ? the question did not mention which side was Hypo . So I chose C because Statement 1 gave the HYPO and confirmed that the other two sides are base and height . and so from statement 2 , we could get va;ue of xy Please let me know your opinion .



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Re: If x and y are the lengths of the legs of a right triangle, what is th
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11 May 2019, 07:34
Bunuel wrote: If x and y are the lengths of the legs of a right triangle, what is the value of xy ?
(1) The hypotenuse of the triangle is \(10\sqrt{2}\). (2) The area of the triangular region is 50.
Given: x and y are the lengths of the legs of a right triangle We have something like this: Target question: What is the value of xy? Statement 1: The hypotenuse of the triangle is \(10\sqrt{2}\). There are infinitelymany different right triangles that meet this condition. Here are two: Case a: x = 10 and y = 10 CHECK: If h = the hypotenuse, then we get 10² + 10² = h² Solve: 200 = h² So, h = √200 = 10√2 In this case, the answer to the target question is xy = (10)(10) = 100Case b: x = √50 and y = √150 CHECK: If h = the hypotenuse, then we get (√50)² + (√150)² = h² Solve: 200 = h² So, h = √200 = 10√2 In this case, the answer to the target question is xy = (√50)(√150) = √7500 = 50√3 Since we cannot answer the target question with certainty, statement 1 is NOT SUFFICIENT Statement 2: The area of the triangular region is 50Area of triangle = (base)(height)/2So, we can write: (x)(y)/2 = 50 Multiply both sides by 2 to get: xy = 100 So, the answer to the target question is xy = 100Since we can answer the target question with certainty, statement 2 is SUFFICIENT Answer: B Cheers, Brent
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Re: If x and y are the lengths of the legs of a right triangle, what is th
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26 Apr 2019, 05:39
The area of the triangle is xy/2, so Statement 2 is immediately sufficient. Statement 1 is not sufficient  if we just draw a hypotenuse of length 10√2, we can make triangles of any small area at all. For example, we might have one leg of length 0.0000001, and another of length just less than 10√2. That triangle will have a tiny area, so xy will be very small. Or this might be a 454590 triangle with legs of length 10, and might have quite a large area.
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Re: If x and y are the lengths of the legs of a right triangle, what is th
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27 Apr 2019, 07:14
Bunuel wrote: If x and y are the lengths of the legs of a right triangle, what is the value of xy ?
(1) The hypotenuse of the triangle is \(10\sqrt{2}\). (2) The area of the triangular region is 50.
DS94602.01 OG2020 NEW QUESTION #1 200= x^2+y^2 insufficient #2 x*y= 100 sufficient IMO B



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Re: If x and y are the lengths of the legs of a right triangle, what is th
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11 May 2019, 08:52
m1033512 wrote: DavidTutorexamPAL wrote: The Logical approach to this question will start by pointing out that since the area of a right triangle is half the product of its legs, then xy is twice the triangle's area. Statement (1) gives us just the hypotenuse. Since the pythagorean theorem is an equation with three variables we must know the value of two of the three in order to solve it (i.e. x² + y² = 200 wouldn't give us neither x not y). Statement (2) is just what we were looking for: xy, as mentioned above, is half the triangular area. The correct answer is (B).
Posted from my mobile device legs of a right angle triangle = two sides other than the Hypo ? the question did not mention which side was Hypo . So I chose C because Statement 1 gave the HYPO and confirmed that the other two sides are base and height . and so from statement 2 , we could get va;ue of xy Please let me know your opinion . Hey m1033512, Yes, a rightangle triangle has 3 sides: two 'legs', which form an angle of 90 degrees between them, and one hypotenuse. So in the equation a^2 + b^2 = c^2 'a' and 'b' are the legs whereas 'c' is the hypotenuse. It isn't necessary to think of a 'base' and 'height' of a rightangle triangle because it doesn't really matter which is which: both legs can be either the base or the height. Best, David
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Re: If x and y are the lengths of the legs of a right triangle, what is th
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11 May 2019, 13:32
Hi All, We're told that X and Y are the lengths of the legs of a RIGHT triangle. We're asked for the value of (X)(Y). This question can be solved with a mix of Geometry rules and TESTing VALUES. (1) The hypotenuse of the triangle is 10√2. With the information in Fact 1  and the Pythagorean Theorem  we can create the following equation: X^2 + Y^2 = (10√2)^2 X^2 + Y^2 = 200 Since this one equation has two variables, it's likely that there are LOTS of different possible values for X and Y  and as a result, there are probably lots of different values for (X)(Y). Here are two examples: IF.... X=10 and Y= 10, then the answer to the question is (10)(10) = 100 X = 9 and Y = √119, then the answer to the question is 9√119 Fact 1 is INSUFFICIENT (2) The area of the triangular region is 50. With the information in Fact 2  and the area formula  we can create the following equation: Area = (1/2)(Base)(Height) 50 = (1/2)(X)(Y) 100 = (X)(Y) This is the exact answer to the question that is asked. Since there's only one possible answer here, there's no more work needed. Fact 2 is SUFFICIENT Final Answer: GMAT assassins aren't born, they're made, Rich
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Re: If x and y are the lengths of the legs of a right triangle, what is th
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14 May 2019, 13:02
m1033512 wrote: DavidTutorexamPAL wrote: The Logical approach to this question will start by pointing out that since the area of a right triangle is half the product of its legs, then xy is twice the triangle's area. Statement (1) gives us just the hypotenuse. Since the pythagorean theorem is an equation with three variables we must know the value of two of the three in order to solve it (i.e. x² + y² = 200 wouldn't give us neither x not y). Statement (2) is just what we were looking for: xy, as mentioned above, is half the triangular area. The correct answer is (B).
Posted from my mobile device legs of a right angle triangle = two sides other than the Hypo ? the question did not mention which side was Hypo . So I chose C because Statement 1 gave the HYPO and confirmed that the other two sides are base and height . and so from statement 2 , we could get va;ue of xy Please let me know your opinion . made the same mistake... i thought any of the two sides can be the legs




Re: If x and y are the lengths of the legs of a right triangle, what is th
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