Question

Plese help, a Inscribed circle D is in a equilateral triangle RTS, RT=12 find the radius of the circle D explain me how you find it please

Answer 1

First, a diagram is needed.
See attached diagram from http://tinyurl.com/m24qbfx

Answer 2

The radius of the inscribed circle is the apothem of the equilateral triangle.

Answer 3

You will need the 30-60-90 theorem. Review the attachments.

Answer 4

The question boils down to this:
What is the length of the 30 leg of a right triangle if the 60 leg of the same triangle has measure 6? That 30 leg (r in the diagram) is the radius of circle D.

Answer 5

Thank you very much

Answer 6

You are welcome.