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How many degrees is angle x?

A normal-level "Angle" problem.Any zigzag between parallel lines yields to one move: draw a parallel line through the bend. It works however many bends there are.

GivenLine ℓ and line m are parallel

Angle ★★★☆☆☆ How many degrees is angle x? 32° 45° x m

Hints

  1. Angle x sits at the point where the line bends. Let's call it P and start there.
  2. Add one construction line: through P, parallel to ℓ and m. Angle x is now split into an upper and a lower part.
  3. When one line crosses two parallel lines, the alternate angles are equal. The new line is parallel to ℓ, so these two angles are the same size.
  4. So the 32° above moves down to the upper side of P, unchanged.
  5. Same below. The new line is parallel to m too, so those alternate angles are equal as well.
  6. So the 45° below moves up to the lower side of P, unchanged.
  7. Angle x is simply those two angles gathered at P, added together.
  8. Just add them. 32° + 45°

Answer 77°

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