In the rhombus ABCD, the length of diagonal BD is 6 and the length of

Question

Tough and Tricky questions: Geometry.

In the rhombus ABCD, the length of diagonal BD is 6 and the length of diagonal AC is 8. What is the perimeter of ABCD?

A. 10 
B. 14 
C. 20 
D. 24 
E. 28

PareshGmat · Accepted Answer

Answer = B Rhombus has equal sides, diagonals bisect each other at 90^{\circ} Refer diagram below rhom.png One side = \sqrt{3^2 + 4^2} = 5 Perimeter = 5*4 = 20

SaharKhan · Answer

* Rhombus has all sides equal.
* The diagonals of Rhombus bisect each other at 90 degrees.

Using these 2nd property we can find the side of the Rhombus = 5 (4^2 + 3^2 = 5^2)
Hence, the Perimeter = 5*4 = 20

Konstantin1983 · Answer

Hi Paresh! I think you meant C not B)

anairamitch1804 · Answer

A rhombus is a parallelogram with four sides of equal length. Thus, AB = BC = CD = DA.

The diagonals of a parallelogram bisect each other, meaning that AC and BD intersect at their midpoints, which we will call E. Thus, AE = EC = 4 and BE = ED = 3. Since ABCD is a rhombus, diagonals AC and BD are also perpendicular to each other.

Labeling the figure with the lengths above, we can see that the rhombus is divided by the diagonals into four right triangles, each of which has one side of length 3 and another side of length 4.

Remembering the common right triangle with side ratio = 3: 4: 5, we can infer that the unlabeled hypotenuse of each of the four triangles has length 5.

Thus, AB = BC = CD = DA = 5, and the perimeter of ABCD is 5 × 4 = 20.

The correct answer is C.

BrentGMATPrepNow · Answer

In a rhombus, the diagonals are perpendicular bisectors. 
 https://i1168.photobucket.com/albums/r500/GMATPrepNow/rhmbs1_zps1nyufj6q.png

So, we can add our lengths as follows. 
 https://i1168.photobucket.com/albums/r500/GMATPrepNow/rhmbs2_zpskyv3wwkl.png

From here, if we focus on one of the 4 right triangles....
 https://i1168.photobucket.com/albums/r500/GMATPrepNow/rhmbs3_zps3riwbumw.png 
...we see we can apply the Pythagorean Theorem to write: 3² + 4² = x²
Evaluate: 9 + 16 = x²
So, 25 = x²
Solve to get: x = 5

Since all 4 sides of a rhombus have equal length, the perimeter = (4)(5) = 20

Answer: C

Cheers,
Brent

Abhishek009 · Answer

Perimeter = 2 \sqrt{p^2 + q^2}

Or,  Perimeter = 2 \sqrt{8^2 + 6^2}

Or,  Perimeter = 2 \sqrt{100}

Or,  Perimeter = 2 *10

Or,  Perimeter = 20 
  
Thus, correct answer will be (C) 20

Nunuboy1994 · Answer

We are given the lengths of the diagonals in the rhombus; therefore, all we need to do is plug in both diagonals into the formula for the side length of a rhombus

The Side Length of a Rhombus
\sqrt{(d1)^2 + (d2)^2}/2
\sqrt{(8)^2 + (6)^2}/2
\sqrt{100}/2
10/2=
5 (because a rhombus is an  equilateral   parallelogram we simply multiply 5 by 4 ( number of the rhombuses sides)

= 20

Thus, "C"

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In the rhombus ABCD, the length of diagonal BD is 6 and the length of

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In the rhombus ABCD, the length of diagonal BD is 6 and the length of

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