HELP MATH EXAM TMR?

Attachment image

4 Answers

Relevance
  • 2 months ago

    19.

    m∠C = 110 answer//

    m∠ B = 80 answer//

    20.

    m∠A = 75 answer//

    m∠D = 90 answer//

    21.

    m∠B = 2/3 answer//

    m∠D = 2/3 answer//

    • Commenter avatarLog in to reply to the answers
  • Pope
    Lv 7
    2 months ago

    Opposite angles of a cyclic quadrilateral are supplementary. That should get you through all of those questions, but I do still have one concern.

    Those given angle measures appear to be in degrees, but no units are given. Normally that is done only for radian measure. The copyright date looks like 1990. Is that how Addison-Wesley still does things? As we say here, that is wrong, with a capital R.

    • Commenter avatarLog in to reply to the answers
  • 2 months ago

    19.

    The sum of two opposite angles of concyclic quadrilateral is 180°.

    m∠B + m∠D = 180

    m∠B + 80 = 180

    m∠B = 100

    m∠C + m∠A = 180

    m∠C + 110 = 180

    m∠C = 70

    ====

    20.

    m∠A + m∠C = 180

    m∠A + 75 = 180

    m∠A = 105

    m∠D + m∠B = 180

    m∠D + 90 = 180

    m∠D = 90

    ====

    21.

    m∠B + m∠D = 180

    m∠B + (2/3)m∠B = 180

    (5/3)m∠B = 180

    m∠B = 108

    m∠D = (2/3)m∠B

    m∠D = (2/3) * 108

    m∠D = 72

    • Commenter avatarLog in to reply to the answers
  • 2 months ago

    since angle A and angle C have the same end points (B and D) and those end points are also on the circle, this means A and C are equal.  Same for D and B.

    Can you figure it out from there?

    • ted s
      Lv 7
      2 months agoReport

      Justin asks too many question each day

    • Commenter avatarLog in to reply to the answers
Still have questions? Get answers by asking now.