help me fill this out thanks

Answer:
j = 7
Step-by-step explanation:
This triangle is a special case triangle: 45-45-90. This means that the two sides next to the right angle are the same length, and that the hypotenuse is that length multiplied by [tex]\sqrt{2[/tex].
In this question, you are given the hypotenuse length, so you know that j must be the hypotenuse divided by [tex]\sqrt{2[/tex]