The swan below is composed of several triangles. Use the given information and the figure to find each angle measure. Note: Figure not drawn to scale.

Given: ΔABC is equilateral; DE¯¯¯¯¯¯¯¯≅CE¯¯¯¯¯¯¯¯≅EF¯¯¯¯¯¯¯¯
\overline{DE}\cong\overline{CE}\cong\overline{EF}; KO¯¯¯¯¯¯¯¯≅FO¯¯¯¯¯¯¯¯
\overline{KO}\cong\overline{FO}; JN¯¯¯¯¯¯¯¯≅JO¯¯¯¯¯¯¯
\overline{JN}\cong\overline{JO}; ∠BCD ≅ ∠BDC; CGF ≅ ∠CFG; ∠HKN ≅ ∠HNK; ΔGCF ≅ ΔGKF ≅ ΔJHM; ΔKFH ≅ ΔKLH

Triangular Swan Portfolio

Print the document so that you can write on it and mark the pictureshowin congruent sides​

(2 points)
1. m∠ABC =

2. m∠BCA =

3. m∠CAB =

4. m∠BCD =

5. m∠BDC =

6. m∠CBD =

1 answer

To find the angle measures for the given triangles and properties of the swan, we'll use the information provided along with some basic properties of triangles and isosceles triangles.

Given Information:

  1. ΔABC is equilateral, meaning:

    • m∠ABC = m∠BCA = m∠CAB
    • Since it is equilateral, each angle measures 60 degrees.
  2. DE ≅ CE ≅ EF:

    • Triangles involving these segments will be isosceles.
  3. KO ≅ FO:

    • Triangles involving these segments will also be isosceles.
  4. JN ≅ JO:

    • Similar to the above, these segments create isosceles triangles.
  5. ∠BCD ≅ ∠BDC:

    • This indicates that triangle BCD is isosceles with the equal angles being ∠BCD and ∠BDC.
  6. CGF ≅ ∠CFG:

    • Another isosceles triangle with base angles that are equal.
  7. ∠HKN ≅ ∠HNK:

    • Yet another isosceles triangle.
  8. ΔGCF ≅ ΔGKF ≅ ΔJHM:

    • These triangles are congruent to each other.
  9. ΔKFH ≅ ΔKLH:

    • These triangles are also congruent to each other.

Calculation of Angles:

  1. m∠ABC = 60°
  2. m∠BCA = 60°
  3. m∠CAB = 60°

Since triangle ABC is equilateral, all angles are 60 degrees.

Next, we'll calculate the angles in triangle BCD, which is isosceles, since ∠BCD ≅ ∠BDC.

Let m∠BCD = x and m∠BDC = x. The third angle, ∠CBD, can be found using the triangle sum theorem (180 degrees):

  • \( m∠BCD + m∠BDC + m∠CBD = 180° \)
  • \( x + x + m∠CBD = 180° \)
  • \( 2x + m∠CBD = 180° \)

We also know that since ∠BCD ≅ ∠BDC, the angles must also add up to 180°. Thus:

  1. To determine x:

    • Since we don't have specific angles from the diagram, we can assume a common measure for the angles.
    • Let's assume x = 70° (as an example), then:
    • \( 2(70°) + m∠CBD = 180° \)
    • \( 140° + m∠CBD = 180° \)
    • \( m∠CBD = 40° \)
  2. m∠BCD = 70°

  3. m∠BDC = 70°

  4. m∠CBD = 40°

Final Angles:

  1. m∠ABC = 60°
  2. m∠BCA = 60°
  3. m∠CAB = 60°
  4. m∠BCD = 70° (hypothetical)
  5. m∠BDC = 70° (hypothetical)
  6. m∠CBD = 40° (hypothetical)

Please adjust the second set of angles based on the actual figure or any additional context provided in your drawings or descriptions.