Answer:
(9[tex]\sqrt{2}[/tex])/2
Step-by-step explanation:
a diagonal divides the square into two right-angle triangles. Given that the two sides are the same length, and the hypothenuse is 9 cm, this applies:
2(a^2) = b^2 (a = side, b = hypothenuse)
2(a^2) = 9^2 (find for a)
2(a^2) = 81
a^2 = 81/2
a =[tex]\sqrt{81/2}[/tex]
a = (9[tex]\sqrt{2}[/tex])/2 or 6.3639 (rounded)
