pls help if u do urrr the best!!

Answer:
2.6
Step-by-step explanation:
we know by Pythagoras theorem that
[tex]a^2+b^2=c^2[/tex]
so for our triangle we have
[tex]a=6\\\\b=b\\\\c=7\\\\\\\\6^2+b^2=7^2\\\\b^2=7^2-6^2\\\\b^2=(7-6)(7+6)\\\\b^2=1(13)\\\\b=\sqrt{13}\\\\b\approx 2.6[/tex]