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Sub 505 (Easy)|   Geometry|      
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fozzzy
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In the figure above, what is the value of x? 04 Sep 2013, 00:44
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B
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5% (low)

Question Stats:

91% (01:06) correct 9% (01:33) wrong based on 143 sessions

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Attachment:
image figure.jpg
image figure.jpg [ 9.5 KiB | Viewed 6559 times ]
In the figure above, what is the value of x?

A) 18
B) 30
C) 36
D) 40
E) 45
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B
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In the figure above, what is the value of x? 04 Sep 2013, 01:09
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Form the equation 4x = 90 + x (Vertically Opp. Angles)
and solve x = 30
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In the figure above, what is the value of x? 04 Sep 2013, 07:30
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can you explain in detail?
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Marcab
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In the figure above, what is the value of x? 04 Sep 2013, 07:43
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fozzzy
can you explain in detail?
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The sole angle x is part of a 90 degree setup, so the remaining value of the setup is 90-x.
The angle 4x is part of 180 degree setup. The remaining angle is 180-4x.
These two angles i.e. 90-x and 180-4x are actually the same. Hence on equating these two, we get the value of x as 30.
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In the figure above, what is the value of x? 04 Sep 2013, 07:55
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fozzzy
can you explain in detail?
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Attachment:
Angles.png
Angles.png [ 8.62 KiB | Viewed 6381 times ]
In the figure above, what is the value of x?

A) 18
B) 30
C) 36
D) 40
E) 45

Look at the diagram above. The red angles are equal: x+90=4x --> x=30.

Answer: B.
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In the figure above, what is the value of x? 25 Sep 2019, 18:44
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fozzzy
Attachment:
image figure.jpg
In the figure above, what is the value of x?

A) 18
B) 30
C) 36
D) 40
E) 45
Show more

4x+(90-x) = 180
x=30

IMO B

Posted from my mobile device
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In the figure above, what is the value of x? 14 Oct 2019, 14:46
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fozzzy
Attachment:
image figure.jpg
In the figure above, what is the value of x?

A) 18
B) 30
C) 36
D) 40
E) 45
Show more


If you extend the perpendicular line, you will realise that the 4x can be broken into 3x and x. And then that 3x represents the 90 degress.
which makes x as 30
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In the figure above, what is the value of x? 26 Feb 2022, 10:45
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The figure shows opposite angles at the vertex.

Remember that: angles opposite the vertex are equal.

So we have to:

90 + x = 4x
X = 30°

Answer B
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In the figure above, what is the value of x? 26 Feb 2022, 11:18
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4x and (90+x) are measures of vertical angles, and, by definition, they are equal.

One can quickly solve x to be 30 degrees.
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