HELP ME PLEASE THIS IS TOO MUCH FOR ME its 2 questions

Answer:
You got the answer right.
The first question BC is 5 cm.
In the second question, we gotta find the hypotenuse.
In a 45 45 90 triangle, the hypotenuse will have a length of [tex]x\sqrt{2}[/tex], therefore, the side AC is equal to [tex]10\sqrt{2}[/tex].