Geometry

Given: in triangle ABC, angle B= 120 degrees
Prove: angle A does not= 60 degrees
Plan: use indirect proof

Assume temporarily that Measure angle A = 60. Then measure angle C=60,
and measure angles A+B+C=180= 60+B+60=180. Therefore the temporary assumption that measure angle A=60 is false. It fallows that measure angle A does not equal 60 degrees.



excellent.

  1. 👍 0
  2. 👎 0
  3. 👁 341
  1. A pap

    1. 👍 0
    2. 👎 0
    posted by Melanie

Respond to this Question

First Name

Your Response

Similar Questions

  1. Math

    Which of the following values best approximates of the length of c in triangle ABC where c = 90(degrees), b = 12, and B = 15(degrees)? c = 3.1058 c = 12.4233 c = 44.7846 c = 46.3644 In triangle ABC, find b, to the nearest degree,

    asked by Max on January 26, 2018
  2. Geometry

    Please answer at least one . PLEASE 1. Triangle XYZ has a right angle at Y. V,W are on XZ such that XV=XY. WZ=YZ, find ANGLE VYW . 2. STUVWXYZ is a regular octagon. Find SW/ TZ. 3. The interior angles of a convex polygon form an

    asked by Jayden on October 19, 2013
  3. Math

    1. Hannah drew a pattern using only equilateral triangles. Which of the following statements about the angles is an equilateral triangle is true? A. The measurement of each angle is 60 degrees** B. The measurement of each angle is

    asked by Megan on February 25, 2016
  4. Genius Math

    Triangle ABC has AC=BC, angle ACB=96 degrees. D is a point in ABC such that angle DAB=18 degrees and angleDBA=30 degrees. What is the measure in degrees of angle ACD? I got 42 degrees!

    asked by Anonymous on December 24, 2013
  5. MATH_URGENT

    Point X is on side \overline{AC} of \triangle ABC such that \angle AXB =\angle ABX, and \angle ABC - \angle ACB = 39 degrees. Find \angle XBC in degrees.

    asked by RhUaNg on March 13, 2014
  6. mathematics

    if AD biscepts angle A in right triangle ABC what is the value of X 1. 60 degrees 2. 90 degrees 3. 100 degrees 4. 120 degrees show work

    asked by ashadaine on December 27, 2011
  7. MATH

    In a triangle ABC, angle A is 2 times angles C and angle B is 20 degrees less than angle C find the number of degrees in these angles In a triangle ABC, angle A is 2 times angles C and angle B is 20 degrees less than angle C find

    asked by fiaie on August 24, 2006
  8. PLEASE HELP!!!!! (Right Triangle Question)

    Point N is on hypotenuse BC of triangle ABC such than angle CAN is 45 degrees. If AC=8 and AB=6, find AN. I did Pythagorean Theorem for triangle ABC, and hypotenuse BC will be 10. I don't know how to continue from there. Oh, I'm

    asked by My Name Is Bob on April 9, 2012
  9. help math

    In triangle ABC, points D,E,F are on sides BC,CA,AB respectively such that AD,BE,CF are angle bisectors of triangle ABC. The linesAD,BE,CF are concurrent at I,the incenter of triangle ABC. If Angle BAC=90, what is the measure (in

    asked by andrew on May 28, 2013
  10. Geometry

    ABC is an acute angle triangle with points D and E on BC and AC, respectively such that BE and AD are altitudes. AD and BE intersect at H. If \angle BCA = 39 ^\circ and \angle EBA = 2 \angle DAB , what is the measure of \angle

    asked by John on March 1, 2013

More Similar Questions