In the figure above, L2 is perpendicular to L1 . Which of the followi

Question

https://gmatclub.com/forum/download/file.php?id=36380 In the figure above, L2 is perpendicular to L1. Which of the following must be true? I. a = 70 II. If a = 70, then b = 20 III. If b = 20, then a = 70 (A) I only (B) II only (C) III only (D) II and III only (E) I, II and III 2017-07-19_1425.png

tinayni552 · Answer

1) a=70, this could be true, but "a" can take any value between 0 and 90 degrees. False
2) Since "L2" is perpendicular to "L1", then they form a 90 degrees angle, so "a+b" should be always equal to 90, a+b=70+20=90, True
3) Same reasoning as above, a+b=20+70=90. True

The answer is (D)

OptimusPrepJanielle · Answer

I. a = 70
II. If a = 70, then b = 20
III. If b = 20, then a = 70

Statement 1 may or may not be true always
Statement 2 and 3 will always be true because the sum of a and b will be 90

Correct Option: D

shanky315 · Answer

Looking at the question. Option 1 can be easily ruled out as angle a can take any value (figure not drawn to scale) ,hence ll and III looks correct. Ans. D.

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JeffTargetTestPrep · Answer

Using the figure above, we see that a + b = 90.

Let’s analyze each Roman numeral.

I. a = 70

Since we know only that the sum of a and b is 90, we cannot determine whether a = 70. Roman numeral I does not have to be true.

II. If a = 70, then b = 20

Since the sum of a and b is 90, if a = 70, then b = 20. II is true.

III. If b = 20, then a = 70

For the same reasons mentioned in II, III is true.

Answer: D

ZahidPavel · Answer

In the figure above, L2 is perpendicular to L1. Which of the following must be true?

I. a = 70
II. If a = 70, then b = 20
III. If b = 20, then a = 70

(A) I only 
(B) II only 
(C) III only
(D) II and III only 
(E) I, II and III

based on figure, a+b = 90
only II and III fulfill that condition
So, Answer must be: D

In the figure above, L2 is perpendicular to L1 . Which of the followi

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In the figure above, L2 is perpendicular to L1 . Which of the followi

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