Deltoid Practice Problems: Kite Properties & Solutions

Master deltoid geometry with step-by-step practice problems. Learn kite properties, diagonal calculations, area formulas, and perimeter solutions.

📚What You'll Master in This Deltoid Practice Session
  • Identify deltoids using the two pairs of equal adjacent sides rule
  • Calculate deltoid area using the diagonal product formula divided by two
  • Find missing angles using base angle equality and vertex angle properties
  • Apply Pythagorean theorem to solve diagonal length problems in kites
  • Determine perimeter by adding all four sides of the deltoid
  • Distinguish between convex and concave deltoid types in geometric problems

Understanding Deltoid

Complete explanation with examples

The Deltoid and Everything You Need to Know to Verify It

What is a Kite or Deltoid?

In geometry, a deltoid is defined as a quadrilateral consisting of 2 2 isosceles triangles that share a common base.

So, what is the identification of a deltoid in the family of quadrilaterals?

A quadrilateral that has 2 pairs of equal adjacent sides

Example:

If given : AD=AB,DC=BC AD=AB,DC=BC

Then: ABCD ABCD is a deltoid by definition.

  • 2 isosceles triangles with a common base form a deltoid.
  • The sum of the angles in the deltoid is 360° 360° degrees.
  • The area of the deltoid contains the number of quadrilaterals that cover the selected parts of the plane.
  • The perimeter of the deltoid is the length of the thread with which we border the outline of the deltoid and is measured in units of length in meters or cm.
3 - Convex Kite

Detailed explanation

Practice Deltoid

Test your knowledge with 49 quizzes

Look at the deltoid in the figure:

555666

What is its area?

Examples with solutions for Deltoid

Step-by-step solutions included
Exercise #1

ABDC is a deltoid.

AB = BD

DC = CA

AD = 12 cm

CB = 16 cm

Calculate the area of the deltoid.

161616121212CCCAAABBBDDD

Step-by-Step Solution

First, let's recall the formula for the area of a rhombus:

(Diagonal 1 * Diagonal 2) divided by 2

Now we will substitute the known data into the formula, giving us the answer:

(12*16)/2
192/2=
96

Answer:

96 cm²

Video Solution
Exercise #2

Shown below is the deltoid ABCD.

The diagonal AC is 8 cm long.

The area of the deltoid is 32 cm².

Calculate the diagonal DB.

S=32S=32S=32888AAABBBCCCDDD

Step-by-Step Solution

First, we recall the formula for the area of a kite: multiply the lengths of the diagonals by each other and divide the product by 2.

We substitute the known data into the formula:

8DB2=32 \frac{8\cdot DB}{2}=32

We reduce the 8 and the 2:

4DB=32 4DB=32

Divide by 4

DB=8 DB=8

Answer:

8 cm

Video Solution
Exercise #3

Indicate the correct answer

The next quadrilateral is:

AAABBBCCCDDD

Step-by-Step Solution

Initially, let us examine the basic properties of a deltoid (or kite):

A quadrilateral is classified as a deltoid if:

  • It has two distinct pairs of adjacent sides that are equal in length.

In the question's image, we observe the following:

  • There are lines connecting A to B, B to C, C to D, and D to A, suggesting a typical quadrilateral.
  • The shape, given its central symmetry (as it is formed by joining these particular points which extend equal lines), is reminiscent of a symmetric or bilaterally mirrored formation.
  • Given the symmetry, it suggests all internal angles are less than 180 degrees, confirming the figure as a convex shape.

From this analysis, the quadrilateral satisfies the characteristic of having pairs of equal adjacent sides which confirms it as a deltoid. The symmetry suggests it is not concave (which occurs when at least one interior angle is greater than 180 degrees).

Therefore, the given quadrilateral, based on its properties and symmetry, is a convex deltoid.

Answer:

Convex deltoid

Video Solution
Exercise #4

True or false:

A deltoid is composed of an isosceles triangle and a right triangle.

Step-by-Step Solution

In order to answer the question we must recall some properties of the deltoid. For this purpose, let's draw the deltoid ABCD ABCD where we connect every two non-adjacent vertices (meaning - draw the diagonals) and mark the intersection of the diagonals with the letter E E :

AAABBBCCCDDDEEE

Let's recall two properties of the deltoid that will help us answer the question ( from the previous drawing):

a. Definition of a deltoid - A deltoid is a convex quadrilateral with two pairs of adjacent equal sides:

BA=BCDA=DC BA=BC\\ DA=DC

b. The diagonals in a deltoid are perpendicular to each other:

ACBDBEA=AED=DEC=CEB=90° AC\perp BD\\ \updownarrow\\ \sphericalangle BEA= \sphericalangle AED= \sphericalangle DEC= \sphericalangle CEB=90\degree

Now we can clearly answer the question that was asked, and the answer is that the deltoid can indeed be described as composed of two isosceles triangles since triangles: ABC,ADC \triangle ABC,\hspace{6pt}\triangle ADC are isosceles - (from property a' mentioned earlier):

AAABBBCCCDDDEEE

Or can be described as composed of four right triangles, since triangles: AEB,CEB,AED,CED \triangle AEB,\hspace{6pt}\triangle CEB,\hspace{6pt}\triangle AED,\hspace{6pt}\triangle CED are right triangles (from property b' mentioned earlier):

AAABBBCCCDDDEEE

Therefore, the correct answer is answer a'.

Answer:

False.

Video Solution
Exercise #5

Look at the deltoid in the figure:

777444

What is its area?

Step-by-Step Solution

Let's begin by reminding ourselves of the formula for the area of a kite

Diagonal1×Diagonal22 \frac{Diagonal1\times Diagonal2}{2}

Both these values are given to us in the figure thus we can insert them directly into the formula:

(4*7)/2

28/2

14

Answer:

14

Video Solution

Frequently Asked Questions

How do you identify if a quadrilateral is a deltoid or kite?

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A quadrilateral is a deltoid (kite) if it has two pairs of equal adjacent sides. For example, if AB = AD and BC = DC, then ABCD is a deltoid. This creates two isosceles triangles sharing a common base.

What is the formula for calculating the area of a deltoid?

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The area of a deltoid equals (d₁ × d₂) ÷ 2, where d₁ and d₂ are the lengths of the two diagonals. The diagonals are perpendicular to each other, making this formula applicable to all kite shapes.

Why are the base angles equal in a deltoid?

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Base angles are equal because a deltoid consists of two congruent isosceles triangles sharing a common base. In isosceles triangles, the base angles are always equal, so corresponding base angles in the deltoid are also equal.

How do you find the perimeter of a kite shape?

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Add all four sides of the deltoid: Perimeter = AB + BC + CD + DA. Since adjacent sides are equal in pairs, you can also use: Perimeter = 2(side₁ + side₂), where side₁ and side₂ are the lengths of the different adjacent sides.

What are the key properties of deltoid diagonals?

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Deltoid diagonals have three main properties: 1) They are perpendicular to each other, 2) The main diagonal bisects both vertex angles, 3) The main diagonal bisects the secondary diagonal at their intersection point.

What's the difference between convex and concave kites?

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A convex kite has both diagonals inside the shape, creating a traditional kite appearance. A concave kite has one diagonal extending outside the shape, creating a bowl-like or dart appearance with an inward-pointing vertex.

How do you solve for missing diagonal lengths in deltoid problems?

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Use the Pythagorean theorem in the right triangles formed by the perpendicular diagonals. If you know the area and one diagonal, use Area = (d₁ × d₂) ÷ 2 to find the other diagonal. The diagonal intersection creates four right triangles.

Can a rhombus or square be considered a special type of deltoid?

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Yes, both rhombus and square are special cases of deltoids. A rhombus is an equilateral kite where all sides are equal. A square is a kite with equal sides and right angles, maintaining the two pairs of equal adjacent sides property.

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