The sum of the interior angles of a pentagon is 540°.
We can use this information to find the value of x by adding the rest of the interior angles and then substracting them from 540°:
[tex]\begin{gathered} 90+90+100+105+x=540 \\ 385+x=540 \\ x=540-385 \\ x=155 \end{gathered}[/tex]
It means that the correct answer is b. 155.
