A walkway forms one diagonal of a square playground. The walkway is 30m long. How long is a side of the​ playground?

Answer 1

Let a = each side of playground

Diagonal = sqrt (a² +a² ) = 30

2a² = 900

a² = 450

a= sqrt (450) = 21.21 m

Answer 2

Since it is a square being split diagonally, we can think of this like two congruent right triangles with a hypotenuse of 30 and two congruent legs.

a²+b²=30²

a²+b²=900

Since we know a and b are equal, we can then rewrite it as

a²+a²=900 or

2a²=900

a²=450

Take the square root of each side and...

a=√450

a=√225*√2

a=15√2

a ≈ 21.213