Find the missing angle for the irregular polygon. show your work.

Answer:
Sum of the interior angles=900º
x=80º
∠A=110º
∠C=130º
∠E=125º
Step-by-step explanation:
The shape is a heptagon. Meaning, the sum of the interior angles is 180º(n-2) where n is the number of sides. So, 180º(7-2)=180º(5)=900º.
So, we can add up all the angles.
x+30º+140º+x+50º+115º+x+45º+140º+140º=900º
3x+660º=900º
3x=240º
x=80º
Then, we can substitute for ∠A, ∠C, and ∠E
∠A=80+30=110º
∠C=80+50=130º
∠E=80+45=125º