whats the answer of this one and why
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Someone please respond to the following query:
The area of the right triangle ABC is 4 times greater than the area of the right triangle KLM.
1) x is 4 times y.
2) x is 4 times greater than y.
How are two different? Please clarify.
Thanks
Mankey
The area of the right triangle ABC is 4 times greater than the area of the right triangle KLM.
1) x is 4 times y.
2) x is 4 times greater than y.
How are two different? Please clarify.
Thanks
Mankey
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Statement 1:
THis in addition with the problem statement makes the Triangles similar this is sufficient to answer the question
Statement 2: Gives only the area of ABC=96=1/2x*y which can have several combinations. SO insufficient
THis in addition with the problem statement makes the Triangles similar this is sufficient to answer the question
Statement 2: Gives only the area of ABC=96=1/2x*y which can have several combinations. SO insufficient
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The formula for the Area of a triangle is 1/2 BASE X ALTITUDE.
Stmt 1 : If the angles ABC and KLM are equal, the triangles are similar triangles.
1/2 BC * AC = 4 * 1/2* LM * KM
BC * AC = 4 LM * KM
= 2 LM * 2 KM
Observe that the length of sides double when the Area increases (SIMILAR TRIANGLES)
Hence the Hypotenuse will be 2* 10 inches = 20 inches.
Stmt 2 : LM = 6 inches. Not sufficient because the length does one ensure they are similar triangles.
Hence Ans A.
Stmt 1 : If the angles ABC and KLM are equal, the triangles are similar triangles.
1/2 BC * AC = 4 * 1/2* LM * KM
BC * AC = 4 LM * KM
= 2 LM * 2 KM
Observe that the length of sides double when the Area increases (SIMILAR TRIANGLES)
Hence the Hypotenuse will be 2* 10 inches = 20 inches.
Stmt 2 : LM = 6 inches. Not sufficient because the length does one ensure they are similar triangles.
Hence Ans A.
- ronnie1985
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s1 says that the trianagles are similar and hence can find the sides of each of the triangle using trigonometric equations
s2 only tells us about triangle KLM, nothing is known about triangle ABC
Hence (A) is ans
s2 only tells us about triangle KLM, nothing is known about triangle ABC
Hence (A) is ans
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- ronnie1985
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S1 is sufficient as by two angles are same means the triangles are similar and then by using trigonometric relations, one can find the hypotenuse of the other triangle
(A) is the answer
(A) is the answer
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Sorry, to chime in on this, as it almost seems irrelevant to the conversation, Statement (1) indicates that ABC and KLM both = 55 degrees. Does it matter where the sides are positioned or where the vertex is that measures the 55 degrees. I may be thinking into it too much, but just want to understand the only items I need to determine if it can be answered. Thanks!
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1 => x=4ymankey wrote:The area of the right triangle ABC is 4 times greater than the area of the right triangle KLM.
1) x is 4 times y.
2) x is 4 times greater than y.
How are two different? Please clarify.
Thanks.
2 => means x-y=4y => x=5y
- chris558
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So we should have memorized the common right triangle sides... 3:4:5-->6:8:10. From the prompt, we know that right triangle KLM has sides 6:8:10. This isn't necessary information, it's just good to realize it.
The rule that is important to know is:
With similar triangles, the ratio of area= s^2:s^2
We DON'T know is whether these are similar triangles. If they are (all their angles are the same), then we can figure this problem out.
1) Since we already know they're both right traingles, it means that one of their angles is 90 degrees. If they both also have a 66 degree angle, it means that their last angle is 35. Then YES, these two triangles ARE SIMILAR. SUFFICIENT.
2) We already know this from the prompt. Nothing new here.. INSUFFICIENT.
A is correct.
The rule that is important to know is:
With similar triangles, the ratio of area= s^2:s^2
We DON'T know is whether these are similar triangles. If they are (all their angles are the same), then we can figure this problem out.
1) Since we already know they're both right traingles, it means that one of their angles is 90 degrees. If they both also have a 66 degree angle, it means that their last angle is 35. Then YES, these two triangles ARE SIMILAR. SUFFICIENT.
2) We already know this from the prompt. Nothing new here.. INSUFFICIENT.
A is correct.
Properties of Similar Triangles:
"¢ Corresponding angles are the same.
"¢ Corresponding sides are all in the same proportion.
"¢ It is only necessary to determine that two sets of angles are identical in order to conclude that two triangles are similar; the third set will be identical because all of the angles of a triangle always sum to 180º.
"¢ If two similar triangles have sides in the ratio x/y, then their areas are in the ratio x^2/y^2.
Statement 2
Angles ABC and KLM are each equal to 55 degrees --> ABC and KLM are similar triangles --> area(ABC)/area(KLM) = 1/4, so the sides are in ratio 2/1 --> hypotenuse KL=10 --> hypotenuse AB=2*10=20.
Sufficient
Statement 1
LM is 6 inches --> KM=8 --> area(KLM) = 24 --> area(ABC) = 96. But just knowing the area of ABC is not enough to determine hypotenuse AB. For instance: legs of ABC can be 96 and 2 OR 48 and 4 and you'll get different values for hypotenuse.
Not sufficient
A
"¢ Corresponding angles are the same.
"¢ Corresponding sides are all in the same proportion.
"¢ It is only necessary to determine that two sets of angles are identical in order to conclude that two triangles are similar; the third set will be identical because all of the angles of a triangle always sum to 180º.
"¢ If two similar triangles have sides in the ratio x/y, then their areas are in the ratio x^2/y^2.
Statement 2
Angles ABC and KLM are each equal to 55 degrees --> ABC and KLM are similar triangles --> area(ABC)/area(KLM) = 1/4, so the sides are in ratio 2/1 --> hypotenuse KL=10 --> hypotenuse AB=2*10=20.
Sufficient
Statement 1
LM is 6 inches --> KM=8 --> area(KLM) = 24 --> area(ABC) = 96. But just knowing the area of ABC is not enough to determine hypotenuse AB. For instance: legs of ABC can be 96 and 2 OR 48 and 4 and you'll get different values for hypotenuse.
Not sufficient
A
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