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The vertex angle of an isosceles triangle is 9 degrees more than a base angle what is the vertex angle?

Answers

  • Réponse publiée par: elaineeee
    66° vertex angle
    base angles 57°
  • Réponse publiée par: homersoncanceranguiu

    Step-by-step explanation:

    let the equal angle of the isosceles triangle be x

    the vertex angle is 2x + 20

    sum of all angles of triangle is 180

    x + x + 2x + 20 = 180

    4x + 20 = 180

    4x = 180 - 20

    4x = 160

    x = 160/4

    x = 40°

    the equal angle are 40° and 40°

    the vertex angle = 2x + 20 = 2(40) + 20 = 80 + 20 = 100°

    the three angles are

    40°, 40°, 100°

    hope you get your answer

  • Réponse publiée par: jasminsexy
    You can use the Pythagorean Theorem to obtain the altitude (the unknown side in the middle.)The vertex, B, is split into two equal angles, but you can easily find the vertex angle by first finding one of the base angles.
  • Réponse publiée par: 09389706948
    Try doing what Lashia answered, if not, please comment on this answer for further help. :)
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The vertex angle of an isosceles triangle is 9 degrees more than a base angle what is the vertex ang...