If the perimeter of a square is 20, find the length of a diagonal. Round your answer to the nearest tenth. 7.7
7.1
6.3
8.4

Since a square is equal on all 4 sides, that means each side would be 5, because 20/4=5

so using the Pythagorean thrm (which we can use since a square has all 90 degree angles)

a=5 b=5 c=?

5^2+5^2=c^2
25+25=c^2
50=c^2 *square root both sides*
c= 7.07

So the answer would be 7.1