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Sub 505 (Easy)|   Geometry|      
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In the figure above, ABC is an equilateral triangle and BDC is an isos 24 Aug 2017, 02:09
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In the figure above, ABC is an equilateral triangle and BDC is an isosceles triangle. If x = 47, what is the value of y?

(A) 13
(B) 23
(C) 30
(D) 47
(E) 53

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2017-08-24_1251_001.png
2017-08-24_1251_001.png [ 12.68 KiB | Viewed 10608 times ]
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A
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In the figure above, ABC is an equilateral triangle and BDC is an isos 24 Aug 2017, 02:34
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Bunuel

In the figure above, ABC is an equilateral triangle and BDC is an isosceles triangle. If x = 47, what is the value of y?

(A) 13
(B) 23
(C) 30
(D) 47
(E) 53

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Attachment:
2017-08-24_1251_001.png
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angle DBC = angle DCB = x = 47 (BDC is isosceles triangle)
angle ABC = 60 (ABC is equilateral triangle)
y = angle ABD = ABC - DBC = 60-47 = 13

A
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In the figure above, ABC is an equilateral triangle and BDC is an isos 24 Aug 2017, 02:45
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Ans : a

ABC is an equilateral triangle.

thus angle ABC=60 degree.

Traingle DBC is isosceles triangle .

Thus Angle DBC=47degree as DCB = 47.

Thus angle ABD = 60-47= 13 degree
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In the figure above, ABC is an equilateral triangle and BDC is an isos 24 Aug 2017, 06:33
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Bunuel

In the figure above, ABC is an equilateral triangle and BDC is an isosceles triangle. If x = 47, what is the value of y?

(A) 13
(B) 23
(C) 30
(D) 47
(E) 53

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Attachment:
2017-08-24_1251_001.png
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1. x + y = measure of angle B

Small triangle BCD is isosceles.

Sides BD and BC are equal; angles opposite those sides are equal. Both small angles of triangle BCD = x

2. Equilateral triangle angles A, B, and C all = 60

3. Angle B = 60 = x + y (from #1)
x = 47
60 - 47 = 13 = y

Answer A
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In the figure above, ABC is an equilateral triangle and BDC is an isos 24 Aug 2017, 10:10
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Bunuel

In the figure above, ABC is an equilateral triangle and BDC is an isosceles triangle. If x = 47, what is the value of y?

(A) 13
(B) 23
(C) 30
(D) 47
(E) 53

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2017-08-24_1251_001.png
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1. If X = 47, so the angle in front of this angle will be equal to 47.
2. Since ABC is an equilateral triangle, so each angle should be 60 degrees.
3. 60-47 = 13.

A
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In the figure above, ABC is an equilateral triangle and BDC is an isos 11 Sep 2017, 13:12
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Bunuel

In the figure above, ABC is an equilateral triangle and BDC is an isosceles triangle. If x = 47, what is the value of y?

(A) 13
(B) 23
(C) 30
(D) 47
(E) 53

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Angle DBC = x
x+y = 60
y=60-47
y = 13
Option A
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In the figure above, ABC is an equilateral triangle and BDC is an isos 21 May 2019, 20:02
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Bunuel

In the figure above, ABC is an equilateral triangle and BDC is an isosceles triangle. If x = 47, what is the value of y?

(A) 13
(B) 23
(C) 30
(D) 47
(E) 53

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2017-08-24_1251_001.png
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X+y = 60, interior angle of an equilateral triangle.
y= 60-47=13
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In the figure above, ABC is an equilateral triangle and BDC is an isos 22 May 2019, 00:01
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This is a simple question, but how can you tell which two sides of isosceles DBC are equal (because the figure says not drawn to scale)?
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