For the first 6, we see that it is exactly one place behind the decimal point, therefore meaning that it is in the tenths place. The second 6 is three places behind the decimal place making it in the thousandths place. The third and final 6 is one place in front of the decimal, therefore it is in the ones place. Hope this helps!
If n is ten then the expression would change to
2(10)+4
20+4
so your answer would be 24
Im not actually quite sure but i believe it is isosceles