• Stomata
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        2 个月前

        You are right that is 80° so the value of x will be 135°

    • LifeInMultipleChoice@lemmy.dbzer0.com
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      2 个月前

      Nah, the imagery tricks you. 180 degrees to a line. 180 degrees inside a triangle.

      So you can gather the inside unlabeled angle on the triangle on the left is only 80 degrees: (180-[60+40])

      So you then know it’s 100 on the right side of that +35 leaves you with 45 degrees left for the top of the right one.

      180-45=. 135 degrees

      • tetris11@lemmy.ml
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        2 个月前

        Also if you add up all visible angles you get 135, so I’m sold on that alone. No no no, I won’t hear any rebuttals.