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    Old 02-12-2021, 08:56 AM
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    Default Math calculation

    How do I figure the side dimensions of an isosceles triangle which has a hypotenuse of 8 inches? I am putting together blocks on point. I know the dimensions of the side setting triangles, but cannot figure out what size to cut the larger corner pieces. Any math wizards out there? Btw, please don't give me the formula . . . give me the answer. Math is NOT my strong suit!
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    Old 02-12-2021, 09:27 AM
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    There is a chart on quiltville.com that I use. Go to tips and techniques. Then on point settings. It gives you calculations and scroll down. There is a chart of sizes calculated for you
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    Old 02-12-2021, 10:03 AM
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    Here's a chart.
    Attached Thumbnails setting-triangle-sizes.png  
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    Old 02-12-2021, 12:29 PM
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    Thank you both, so much! This is a huge help!!!
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    Old 02-13-2021, 01:18 AM
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    When stuff like this happens to me...I get some newspaper or other scrap paper and build a model. Then cut the fabric 1\2 " larger so I can trim to perfection
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    Old 02-13-2021, 06:37 AM
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    Thanks Peckish, I've printed that chart off and will put it in my reference notebook. Marcia
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    Old 02-13-2021, 07:46 AM
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    Assuming that the isosceles triangle has a right angle (90 degree) since it has a hypotenuse of 8 the formula would be
    a^2 + b^2=c^2
    Where a and b represent the 2 equal sides and c represents the hypotenuse. Pythagorean Theorem.
    "a" squared plus "b" squared = "c" squared
    so if a and b are equal ( a=b) thus isosceles then you have
    2 a^2 = c^2 (2 times "a" (side) squared = "c" (hypotenuse) squared)
    or in your case since you said the hypotenuse was 8 inches
    2 a^2 = 8^2 (2 times "a" squared = 8 squared) or
    2 a^2=64
    You would then divide both sides by 2 leaving
    a^2=32 ("a" squared = 32)
    Take the square root of both sides and the sides of your isosceles triangle are 5.66 inches

    IMHO, the charts are much easier if you can find one that shows the hypotenuse or you know the finished size of the unit.

    Last edited by Stitches23; 02-13-2021 at 07:48 AM.
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    Old 02-13-2021, 06:39 PM
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    I followed Bonnie Hunter's instructions in the Tips and Techniques section of her website, cut out my triangles, and they fit! Thank you to everyone for your kind help!
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