0<4x + 8<12 BADDA-BING-BADDA-BOOM!!! :-)
Answer:
∠ADB≅∠ABC by the Alternate Interior Angles Theorem
∠CAD≅∠ACB by the Alternate Interior Angles Theorem
∠BAD and ∠ADV are supplementary by the Consecutive Interior Angle Theorem
∠ABC and ∠BCD are supplementary by the Consecutive Interior Angle Theorem