• @[email protected]
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    3 days ago

    Sequence of lines to focus on to get to the answer

    making the BOLD ASSUMPTION that the angle of the arch is 90deg (the bottom right corner of your diagram), then the dashed lines will lead you to the value of the bold line.

    If the original assumption is correct, then the answer is 15.

  • @[email protected]
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    5 days ago

    24 and 7 make a pythagorean triple with 25 as the hypotenuse. If the problem uses one pythagorean triple, it probably uses another, so I assume x is 15, and the radius is 20.

      • @[email protected]
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        3 days ago

        This is the worst way to go about doing it, because you should never assume a drawing is made to scale unless it is specifically marked as such. A protractor would be useless if the drawing isn’t to scale. Generally speaking, if a problem isn’t drawn to scale, it’s because all of the info you need to solve it is already present in the drawing. You don’t need to bust out the protractor to measure angles, because the angles can either be calculated from the available info, or aren’t needed in the first place.

        • @[email protected]
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          13 days ago

          I meant more like trying to use cos tan sin and the pythogoras thing not actually measuring it by hand haha

  • @[email protected]
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    156 days ago

    if we assume the bottom right corner is a right angle and is the center of the arc, then it is solvable in the manners that others here have already described. if either of those is not the case, and the image itself doesn’t state, then there is insufficient information to solve it.

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    126 days ago

    I assume you need to calculate the red triangle’s hypotenuse but it seems like there are too many degrees of freedom to lock down any of the other sides or angles of the triangle including X unless I’m missing some hack involving chords and reflected angles.

    • @[email protected]
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      46 days ago

      Try to draw a full semicircle and extend the 7 units long red line, you will notice it falls on the other corner of the semicircle. In fact, every way of drawing two segments from a semicircle corner to the same point if the circumference forms a right triangle.

      Now, on the original figure, draw the hypotenuse of the red triangle, you will notice the hypotenuse is as long as the extension you draw earlier, because both start from the same height and fall on a corner of the same semicircle. That means that you can find the extension by calculating the hypotenuse.

      Now, you can calculate 7+extension to get the cathetes of the extended triangle, and it’s hypotenuse is the diameter of the semicircle. You can divide the diameter by two to get the radius.

      Now, you notice that: X, the radius, and the red hypotenuse form a right triangle, and you know the length of the red hypotenuse and of the radius, so you can find X.

  • @[email protected]
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    96 days ago

    Try to draw a full semicircle and extend the 7 units long red line, you will notice it falls on the other corner of the semicircle. In fact, every way of drawing two segments from a semicircle corner to the same point if the circumference forms a right triangle.

    Now, on the original figure, draw the hypotenuse of the red triangle, you will notice the hypotenuse is as long as the extension you draw earlier, because both start from the same height and fall on a corner of the same semicircle. That means that you can find the extension by calculating the hypotenuse.

    Now, you can calculate 7+extension to get the cathetes of the extended triangle, and it’s hypotenuse is the diameter of the semicircle. You can divide the diameter by two to get the radius.

    Now, you notice that: X, the radius, and the red hypotenuse form a right triangle, and you know the length of the red hypotenuse and of the radius, so you can find X.