Notice that the irregular polygon has 6 sides. Then, we can use the formula for calculating the sum of interior angles:
[tex]S=180(n-2)[/tex]in this case,n = 6, then:
[tex]\begin{gathered} S=180(6-2)=180(4)=720 \\ S=720\degree \end{gathered}[/tex]now that we have that the sum of the interior angles equals 720 degrees, we can find the value of angle x:
[tex]\begin{gathered} 98+90+155+112+140+x=720 \\ \Rightarrow595+x=720 \\ \Rightarrow x=720-595=125 \\ x=125\degree \end{gathered}[/tex]therefore, the measure of angle x is 125 degrees
