• PresidentCamacho@lemm.ee
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    1 month ago

    It pisses me off to no end that what is CLEARLY shown as a 90degree angle is not in fact 90deg, I hate it when they do that.

    Also I will sadly admit this can teach people lessons about verifying the information themselves.

    GrumbleGrumbleGrumble…

    • ngwoo@lemmy.world
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      1 month ago

      Geometry diagrams in math problems should never be assumed to be to scale

    • yannic@lemmy.ca
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      1 month ago

      I get you, but it doesn’t clearly indicate the angle in the middle at the base as much as it suggestively waggles its eyebrows towards 90⁰, it could just as easily be 89.9999999999999⁰, although upon zooming in, you can see the line does shift one pixel over on its way up. You simply can’t trust any of the angles as 90⁰ unless it’s got the ∟ symbol (that’s the official unicode) or you’ve measured them yourself, and with that one pixel off-set, it’s decidedly not 90⁰. That’s why you have to do the math.

      • Denjin@lemmings.world
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        1 month ago

        The internal angles of a triangle always add up to 180⁰, therefore the one pixel offset is irrelevant because the unlabelled angle is, despite what the image suggests, 60 80⁰.

        • sugar_in_your_tea@sh.itjust.works
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          1 month ago

          Assuming you’re talking about the triangle on the left, it’s 80⁰: 180 - 60 - 40 = 80. The other two unlabeled angles are 100⁰ and 45⁰ respectively. None of the unlabelled angles are 60⁰.

    • Letstakealook@lemm.ee
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      1 month ago

      Another way to look at it is that it is simply a representation of an object. We don’t need to visualize the angles, as the values to the other asks are given. We just need the geometry of the object represented so we can calculate the value of the unlabeled angle. Given that the geometry of the objects is represented as triangles, we can infer that all sides are straight lines, regardless of the type of space the object occupies.

    • jj4211@lemmy.world
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      1 month ago

      Actually, it might be a 90 degree angle, but the shape on the left might be a quadrilateral instead of a triangle.