{"appState":{"pageLoadApiCallsStatus":true},"articleState":{"article":{"headers":{"creationTime":"2016-12-08T05:04:12+00:00","modifiedTime":"2016-12-08T05:04:12+00:00","timestamp":"2022-09-14T18:16:42+00:00"},"data":{"breadcrumbs":[{"name":"Academics & The Arts","_links":{"self":"https://dummies-api.dummies.com/v2/categories/33662"},"slug":"academics-the-arts","categoryId":33662},{"name":"Math","_links":{"self":"https://dummies-api.dummies.com/v2/categories/33720"},"slug":"math","categoryId":33720},{"name":"Geometry","_links":{"self":"https://dummies-api.dummies.com/v2/categories/33725"},"slug":"geometry","categoryId":33725}],"title":"How to Copy an Angle Using a Compass","strippedTitle":"how to copy an angle using a compass","slug":"copy-angle-using-compass","canonicalUrl":"","seo":{"metaDescription":"The basic idea behind copying a given angle is to use your compass to sort of measure how wide the angle is open; then you create another angle with the same am","noIndex":0,"noFollow":0},"content":"The basic idea behind copying a given angle is to use your compass to sort of measure how wide the angle is open; then you create another angle with the same amount of opening.\r\n\r\n<a href=\"https://www.dummies.com/wp-content/uploads/GEOM-3E_0046_01.gif\"><img class=\"alignnone wp-image-230074 size-full\" src=\"https://www.dummies.com/wp-content/uploads/GEOM-3E_0046_01.gif\" alt=\"geometry-angle-compass\" width=\"251\" height=\"45\" /></a>\r\n\r\nHere's the proof diagram.\r\n\r\n[caption id=\"attachment_229613\" align=\"aligncenter\" width=\"400\"]<a href=\"https://www.dummies.com/wp-content/uploads/9781119181552-fg2008.gif\"><img class=\"wp-image-229613 size-full\" src=\"https://www.dummies.com/wp-content/uploads/9781119181552-fg2008.gif\" alt=\"geometry-copying-angle\" width=\"400\" height=\"536\" /></a> Copying an angle.[/caption]\r\n\r\nRefer to the figure as you work through these steps:\r\n<ol>\r\n\t<li>Draw a working line, l, with point B on it.</li>\r\n\t<li>Open your compass to any radius r, and construct arc (A, r) intersecting the two sides of angle A at points S and T.</li>\r\n\t<li>Construct arc (B, r) intersecting line l at some point V.</li>\r\n\t<li>Construct arc (S, ST).</li>\r\n\t<li>Construct arc (V, ST) intersecting arc (B, r) at point W.</li>\r\n\t<li>Draw line BW and you're done.</li>\r\n</ol>","description":"The basic idea behind copying a given angle is to use your compass to sort of measure how wide the angle is open; then you create another angle with the same amount of opening.\r\n\r\n<a href=\"https://www.dummies.com/wp-content/uploads/GEOM-3E_0046_01.gif\"><img class=\"alignnone wp-image-230074 size-full\" src=\"https://www.dummies.com/wp-content/uploads/GEOM-3E_0046_01.gif\" alt=\"geometry-angle-compass\" width=\"251\" height=\"45\" /></a>\r\n\r\nHere's the proof diagram.\r\n\r\n[caption id=\"attachment_229613\" align=\"aligncenter\" width=\"400\"]<a href=\"https://www.dummies.com/wp-content/uploads/9781119181552-fg2008.gif\"><img class=\"wp-image-229613 size-full\" src=\"https://www.dummies.com/wp-content/uploads/9781119181552-fg2008.gif\" alt=\"geometry-copying-angle\" width=\"400\" height=\"536\" /></a> Copying an angle.[/caption]\r\n\r\nRefer to the figure as you work through these steps:\r\n<ol>\r\n\t<li>Draw a working line, l, with point B on it.</li>\r\n\t<li>Open your compass to any radius r, and construct arc (A, r) intersecting the two sides of angle A at points S and T.</li>\r\n\t<li>Construct arc (B, r) intersecting line l at some point V.</li>\r\n\t<li>Construct arc (S, ST).</li>\r\n\t<li>Construct arc (V, ST) intersecting arc (B, r) at point W.</li>\r\n\t<li>Draw line BW and you're done.</li>\r\n</ol>","blurb":"","authors":[{"authorId":8957,"name":"Mark Ryan","slug":"mark-ryan","description":" Mark Ryan has taught pre-algebra through calculus for more than 25 years. 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How to Copy an Angle Using a Compass

By: Mark Ryan and

Updated: 12-08-2016

From The Book: Geometry For Dummies

Geometry For Dummies

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The basic idea behind copying a given angle is to use your compass to sort of measure how wide the angle is open; then you create another angle with the same amount of opening.

Here's the proof diagram.

Copying an angle.

Refer to the figure as you work through these steps:

Draw a working line, l, with point B on it.
Open your compass to any radius r, and construct arc (A, r) intersecting the two sides of angle A at points S and T.
Construct arc (B, r) intersecting line l at some point V.
Construct arc (S, ST).
Construct arc (V, ST) intersecting arc (B, r) at point W.
Draw line BW and you're done.

About This Article

This article is from the book:

Geometry For Dummies ,

About the book author:

Mark Ryan is the founder and owner of The Math Center in the Chicago area, where he provides tutoring in all math subjects as well as test preparation. Mark is the author of Calculus For Dummies, Calculus Workbook For Dummies, and Geometry Workbook For Dummies.

This article can be found in the category:

Geometry ,

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