Perimeter of isoceles triangle without the base

[jceriotti]

I have sides a=10 and c=10, but base is unknown. Angles are 120 degress where sides a and c intersect, so the other two angles are 30 degrees. I do not have the altitude either. I am perplexed. Thanks.

 

[mmm4444bot]

I'm sure that I just responded to this exercise elsewhere.

 

[tutor_joel]

You have to bisect this triangle down the 120deg angle creating a 30, 60, 90 triangle with a hypotenuse of 10.

 

[Deleted member 4993]

I have sides a=10 and c=10, but base is unknown. Angles are 120 degress where sides a and c intersect, so the other two angles are 30 degrees. I do not have the altitude either. I am perplexed. Thanks.

Do you know the law of cosine of a triangle?

 

[tutor_joel]

I have sides a=10 and c=10, but base is unknown. Angles are 120 degress where sides a and c intersect, so the other two angles are 30 degrees. I do not have the altitude either. I am perplexed. Thanks.

Do you know the law of cosine of a triangle?

I'm thinking not, since this is an algebra thread