Answer:
3
Step-by-step explanation:
[tex]a^{2} +b^{2} =c^{2}[/tex]
[tex]x^{2} +b^{2} =(3\sqrt{2} )^{2}[/tex]
[tex]3*3=9[/tex][tex]\sqrt{2} *\sqrt{2} =2[/tex]
[tex]2*9=18[/tex]
9*2=18
x^2=9
b^2=9
x=3