Then base on 20 ... and make the height outside the triangle ... and the height can be calculated as 16. ...

The outer triangle of isosceles triangle .. takes 20 as the hypotenuse, 16 as the right angle, and the other hypotenuse can be calculated as 12. ..

In a large right-angled triangle ... take 12+20 as the right-angled side ... 16 as the other right-angled side ... you can calculate the hypotenuse (the bottom of the isosceles triangle) ... 16 times the root number 5 ... because 20+20 >:1. ..

The circumference is 40+ 16 times the root number 5. ....

Then make an isosceles triangle with the base of 20 ... the height is within the triangle ... and the height is also 16.

You can calculate the root number 89 with twice the hypotenuse. ...

Also conforms to the meaning of the problem. ...

The second answer is four times the root number 89+20.