Answer:
x=3
Step-by-step explanation:
we can use the pythagora thearom as it is a right angled triangle.
[tex]a^{2} +b^{2} =c^{2}[/tex]
so in this example it would be like this
[tex]x^{2} +x^{2} =(3\sqrt{2})^{2}[/tex]
so lets simplify it to this
[tex]2x^{2} =18[/tex]
now all thats left is to get x on its own
[tex]x^{2} =9[/tex]
[tex]x=+or-3[/tex]
x cant be -3 so x =3
