We can solve this problem using a Pythagorean theorem.
[tex]c^2=a^2+b^2[/tex]
Where a is 7 and b is 4 and c is the hypothenuse we are looking for.
[tex]
c^2=7^2+4^2\Longrightarrow c=\sqrt{49+16}=\boxed{8.06}
[/tex]
The length of the third side is approximately 8.
Hope this helps.
r3t40
