Concept:Angles formed around a point always add up to 360∘.Explanation:Add all the angles shown in the diagram and set the sum equal to 360∘.(x−10∘)+(4x−50∘)+2x∘+3x∘+20∘=360∘Combine like terms:x+4x+2x+3x=10x−10−50+20=−40So, 10x−40=360.Add 40 to both sides:10x=400Divide both sides by 10:x=40Answer:x=40∘, so the correct option is D.
