Monday
March 27, 2017

Post a New Question

Posted by on .

ABCD is a trapezoid with AB parallel to DC. If AB=25, BC=24, CD=50 and AD=7, what is the area of ABCD?

  • geometry - ,

    We are going to need some sort of angle.

    draw BE || AD, then ABED is a parallelogram and BE = 7
    In triangle BCE,
    BC = 24
    BE = 7
    CE = 50-25 = 25

    by the cosine law:
    7^2 = 24^2 + 25^2 - 2(24)(25)cosC
    cosC = 1152/1200
    angle C = 16.26... ---- I stored the entire number

    we can now find the height:
    sin 16.26... = height/24
    height = 24sin16.26.. = 6.72 --- that came out exact

    area = (1/2)(25+50)(6.72) = 252 square units

Answer This Question

First Name:
School Subject:
Answer:

Related Questions

More Related Questions

Post a New Question