To find the length of r, you set up the equation as sin(45)= 4.9/r. Then you get r by itself changing it to r = 4.9/sin(45). Then you can find that r = 6.9. Since this is an isosceles triangle, n^1 has to be equal to 4.9. Then you add all the side lengths together. 4.9 + 4.9 + 6.9 = 16.7 units
