Answer:
C
Step-by-step explanation:
The diagonal splits the square into 2 right triangles with hypotenuse 6
Using Pythagoras' identity in one of the right triangles.
The square on the hypotenuse is equal to the sum of the squares on the other 2 sides, that is
s² + s² = 6²
2s² = 36 ( divide both sides by 2 )
s² = 18 ( take the square root of both sides )
s = [tex]\sqrt{18}[/tex] = [tex]\sqrt{9(2)}[/tex] = [tex]\sqrt{9}[/tex] × [tex]\sqrt{2}[/tex] = 3[tex]\sqrt{2}[/tex] → C
