Simple geometry question
posted by Anonymous
What do the lines mean that are on certain triangles. for example, a triangle would have a single dash at the bottom, two dashes on one side and three dashes on the other

Anonymous
Working with Equilateral Triangles
Problem 1:
In a paragraph proof format, show why the angles of an equilateral triangle must measure 60 degrees. 
Steve
The dashes mean that the sides are all of different lengths. If two sides have the same length, then they will both have the same number of dashes.
As for the proof, it depends on what you have covered so far. Equal angles are opposite equal sides. Since all the sides are equal, then all the angles must be equal. Since the angles sum to 180 degrees (another proof you will need) they are each 60 degrees.
Respond to this Question
Similar Questions

Math Question
Which one of the following pairs of triangle must be similar? 
Geometry
How do I find the mesurements of a isosceles triangle? 
Math  Geometry
Two right triangles are touching at the tips. The left triangle has the 90 degree angle to the bottom left, and 33 degrees on the bottom right. Based on this info, the other angle is 57 degrees. The right triangle has the right angle … 
math
Samuel Morse developed a character coding system that was used to send messages along telegraph lines and also for light signalling between ships. Morse code is based on a series of dots and dashes (short of long bursts). The most … 
QUOTATION MARKS
Question 1 Which of the following is one reason to use quotation marks in a sentence? 
Geometry Are these two triangles similar? Thanks!
Are these two triangles similar? How do you know? 
geometry
f equilateral triangle JKL is cut by three lines as shown above to form four equilateral triangles of equal area, what is the length of a side of one of the smaller triangles? 
geometry triangles
The sides of a triangle are 8,15 and 18 the shortest side of a similar triangle is 10 how long are the other sides? 
Urgent geometry help
On my test over parallel lines and proportional parts in triangles today, there was a question that asked to solve for x. There was 2 problems with x in them in the triangle. So would I just have to multiply each part by two and set … 
Geometry
The areas of two similar triangles are in the ratio 36:25. If one side of the larger triangle is 60cm, what is the length of the corresponding side of the other triangle?