This is one of the things I need help on?
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Answer:
Here's your solution
=> Both angles are interior angles hence their
=> sum will equal to 180°
=> (2x + 10)° + ( x + 5) = 180°
=> 2x + 10° + x + 5° = 180°
=>.3x + 15° = 180°
=> 3x = 180° - 15°
=>. 3x = 165°
=>. x = 165/3
=>. x = 55°
=> hence angle = 120° and 60°
hope it helps