I’m very happy with how this problem is set up so the student uses the compass to first better understand the symmetry of the figure before finding the area.
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I’m very happy with how this problem is set up so the student uses the compass to first better understand the symmetry of the figure before finding the area. It’s not as trivial as it looks to copy the figure for 9th graders. I’m trying to show them how drawing can be a way of thinking and solving. #education #mathematics #geometry
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I’m very happy with how this problem is set up so the student uses the compass to first better understand the symmetry of the figure before finding the area. It’s not as trivial as it looks to copy the figure for 9th graders. I’m trying to show them how drawing can be a way of thinking and solving. #education #mathematics #geometry
@futurebird ohhohhohh it's an annulus and a half annulus so 3/2 * pr^2 -r^2
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I’m very happy with how this problem is set up so the student uses the compass to first better understand the symmetry of the figure before finding the area. It’s not as trivial as it looks to copy the figure for 9th graders. I’m trying to show them how drawing can be a way of thinking and solving. #education #mathematics #geometry
@futurebird i remember doing compass and streight edge back in high school in the 70s. do schools no longer do this?
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I’m very happy with how this problem is set up so the student uses the compass to first better understand the symmetry of the figure before finding the area. It’s not as trivial as it looks to copy the figure for 9th graders. I’m trying to show them how drawing can be a way of thinking and solving. #education #mathematics #geometry
Because the curve of the S leading up to the other half circle is symmetric I think you can flip it so it's pointing down completing the bottom circle.
Thus you have one circle with a hole in it and one half circle with a half hole in it.
I think the answer is:
3/2 π( 2² - 1²) = 4.5π = 14.137...
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Because the curve of the S leading up to the other half circle is symmetric I think you can flip it so it's pointing down completing the bottom circle.
Thus you have one circle with a hole in it and one half circle with a half hole in it.
I think the answer is:
3/2 π( 2² - 1²) = 4.5π = 14.137...
I think of it as two 3/4 donuts
S AREA = 2*donut*(3/4)
donut=16pi-4pi=12pi
S AREA = 2*12pi*(3/4)
S AREA = 18 piThe squares are 2cm not 1cm
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@futurebird i remember doing compass and streight edge back in high school in the 70s. do schools no longer do this?
Some do. Some don't. I always get a compass in their hands whenever I can.
1. It really helps one to understand geometry in a different deeper way.
2. It's fun and for some students it's a way to do math that will feel different from all of the equations and dividing and chugging along. I find about 2/3s of my students love it... and some are students who haven't found a reason to love anything about math yet. -
F myrmepropagandist shared this topic
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Some do. Some don't. I always get a compass in their hands whenever I can.
1. It really helps one to understand geometry in a different deeper way.
2. It's fun and for some students it's a way to do math that will feel different from all of the equations and dividing and chugging along. I find about 2/3s of my students love it... and some are students who haven't found a reason to love anything about math yet.@futurebird it's always good to engage the body i mathematics. math can be hard (100 yr old problems) so as many modes we can bring to bear...
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Some do. Some don't. I always get a compass in their hands whenever I can.
1. It really helps one to understand geometry in a different deeper way.
2. It's fun and for some students it's a way to do math that will feel different from all of the equations and dividing and chugging along. I find about 2/3s of my students love it... and some are students who haven't found a reason to love anything about math yet.@futurebird @barrygoldman1
in the 1980s, our geometry, analytic geometry, trigonometry, and even algebra books had a few compass and straight edge exercises. (Well, the geometry book had a lot more than a few.) But we were told to skip all that stuff, with the exception of one math teacher who quickly gave up after learning the math department only had about 5 compasses and most students didn't have one.
