to the nearest hundredth of a centimeter what is the length of a leg of the triangle?

The length of a leg (or both legs) is equal to 59.74cm.
Why?
We can calculate the length of a leg of the given triangle, we can use the following formula:
[tex]Sin(\alpha )=\frac{Opposite}{Hypotenuse}[/tex]
We know the angle, and the length of the hypotenuse, so, substituting and calculating we have:
[tex]Sin(45\° )=\frac{Opposite}{84.6cm}\\\\0.707*84.5cm=Opposite\\\\Opposite=59.7415cm=59.74cm[/tex]
Hence, we know that the length of the legs is equal to 59.74cm (it's a right isosceles triangle)
Have a nice day!