{"id":259,"date":"2014-06-10T12:00:13","date_gmt":"2014-06-10T19:00:13","guid":{"rendered":"http:\/\/mostlymental.com\/?p=259"},"modified":"2014-06-10T00:04:39","modified_gmt":"2014-06-10T07:04:39","slug":"pythagoras-week-day-3-2","status":"publish","type":"post","link":"http:\/\/mostlymental.com\/?p=259","title":{"rendered":"Pythagoras Week: Day 3"},"content":{"rendered":"<p>Hello everyone!<\/p>\n<p>Welcome back to Pythagoras Week.\u00a0 If you missed it, be sure to check it out from the <a href=\"http:\/\/mostlymental.com\/?p=243\">beginning<\/a>.\u00a0 Today's proof uses an interesting \"sliding\" property of parallelograms.\u00a0 Essentially, we can take a parallelogram and slide opposite sides parallel to each other without changing the area, as below.\u00a0 It works because the area for a parallelogram is the base times the height, and we aren't changing either by sliding them.<a href=\"http:\/\/mostlymental.com\/wp-content\/uploads\/2014\/06\/parallelogram.png\"><img loading=\"lazy\" decoding=\"async\" class=\"size-medium wp-image-272 aligncenter\" src=\"http:\/\/mostlymental.com\/wp-content\/uploads\/2014\/06\/parallelogram-300x80.png\" alt=\"parallelogram\" width=\"300\" height=\"80\" srcset=\"http:\/\/mostlymental.com\/wp-content\/uploads\/2014\/06\/parallelogram-300x80.png 300w, http:\/\/mostlymental.com\/wp-content\/uploads\/2014\/06\/parallelogram.png 584w\" sizes=\"auto, (max-width: 300px) 100vw, 300px\" \/><\/a><\/p>\n<p>&nbsp;<\/p>\n<p>Now that we have that fact, what can we do with it?\u00a0 Well, let's start with our right triangle, as below.\u00a0 We can place squares on either of the legs, as shown.<a href=\"http:\/\/mostlymental.com\/wp-content\/uploads\/2014\/06\/pyth_proof_3_1.png\"><img loading=\"lazy\" decoding=\"async\" class=\"size-medium wp-image-273 aligncenter\" src=\"http:\/\/mostlymental.com\/wp-content\/uploads\/2014\/06\/pyth_proof_3_1-300x205.png\" alt=\"pyth_proof_3_1\" width=\"300\" height=\"205\" srcset=\"http:\/\/mostlymental.com\/wp-content\/uploads\/2014\/06\/pyth_proof_3_1-300x205.png 300w, http:\/\/mostlymental.com\/wp-content\/uploads\/2014\/06\/pyth_proof_3_1.png 544w\" sizes=\"auto, (max-width: 300px) 100vw, 300px\" \/><\/a>Using the sliding property, we can slide the two squares until they meet, as shown below.<a href=\"http:\/\/mostlymental.com\/wp-content\/uploads\/2014\/06\/pyth_proof_3_2.png\"><img loading=\"lazy\" decoding=\"async\" class=\"size-medium wp-image-274 aligncenter\" src=\"http:\/\/mostlymental.com\/wp-content\/uploads\/2014\/06\/pyth_proof_3_2-300x246.png\" alt=\"pyth_proof_3_2\" width=\"300\" height=\"246\" srcset=\"http:\/\/mostlymental.com\/wp-content\/uploads\/2014\/06\/pyth_proof_3_2-300x246.png 300w, http:\/\/mostlymental.com\/wp-content\/uploads\/2014\/06\/pyth_proof_3_2.png 548w\" sizes=\"auto, (max-width: 300px) 100vw, 300px\" \/><\/a>Then we can just slide the two parallelograms down until they fill the square at the bottom.<a href=\"http:\/\/mostlymental.com\/wp-content\/uploads\/2014\/06\/pyth_proof_3_3.png\"><img loading=\"lazy\" decoding=\"async\" class=\"size-medium wp-image-275 aligncenter\" src=\"http:\/\/mostlymental.com\/wp-content\/uploads\/2014\/06\/pyth_proof_3_3-129x300.png\" alt=\"pyth_proof_3_3\" width=\"129\" height=\"300\" \/><\/a>The original squares had area <span class='MathJax_Preview'><img src='http:\/\/mostlymental.com\/wp-content\/plugins\/latex\/cache\/tex_ebc3d7bedc1f11e08895c3124001cbb5.gif' style='vertical-align: middle; border: none; padding-bottom:1px;' class='tex' alt=\"\" \/><\/span><script type='math\/tex'><\/script> and <span class='MathJax_Preview'><img src='http:\/\/mostlymental.com\/wp-content\/plugins\/latex\/cache\/tex_78142dcc962f15db95107f42abcbfc86.gif' style='vertical-align: middle; border: none; ' class='tex' alt=\"\" \/><\/span><script type='math\/tex'><\/script>, and the final square has area <span class='MathJax_Preview'><img src='http:\/\/mostlymental.com\/wp-content\/plugins\/latex\/cache\/tex_2796af5074a7f27ecccd3cd17e165d53.gif' style='vertical-align: middle; border: none; padding-bottom:1px;' class='tex' alt=\"\" \/><\/span><script type='math\/tex'><\/script>, so we get <span class='MathJax_Preview'><img src='http:\/\/mostlymental.com\/wp-content\/plugins\/latex\/cache\/tex_d459699ab031562a6c4fbb577db204bc.gif' style='vertical-align: middle; border: none; ' class='tex' alt=\"\" \/><\/span><script type='math\/tex'><\/script>.<\/p>\n<p>&nbsp;<\/p>\n<p>I've glossed over a lot of steps here because I want to get the big picture across, but if you'd like me to fill in the details, I'm happy to explain in the comments.<\/p>\n<p>That's it for today.\u00a0 Tune in tomorrow for another proof.<\/p>\n<a class=\"synved-social-button synved-social-button-share synved-social-size-48 synved-social-resolution-single synved-social-provider-facebook nolightbox\" data-provider=\"facebook\" target=\"_blank\" 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Welcome back to Pythagoras Week.\u00a0 If you missed it, be sure to check it out from the beginning.\u00a0 Today's proof uses an interesting \"sliding\" property of parallelograms.\u00a0 Essentially, we can take a parallelogram and slide opposite sides parallel to each other without changing the area, as below.\u00a0 It works because the area for &hellip; <a href=\"http:\/\/mostlymental.com\/?p=259\" class=\"more-link\">Continue reading <span class=\"screen-reader-text\">Pythagoras Week: Day 3<\/span> <span class=\"meta-nav\">&rarr;<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[4,2],"tags":[],"class_list":["post-259","post","type-post","status-publish","format-standard","hentry","category-geometry","category-math"],"_links":{"self":[{"href":"http:\/\/mostlymental.com\/index.php?rest_route=\/wp\/v2\/posts\/259","targetHints":{"allow":["GET"]}}],"collection":[{"href":"http:\/\/mostlymental.com\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/mostlymental.com\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/mostlymental.com\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"http:\/\/mostlymental.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=259"}],"version-history":[{"count":2,"href":"http:\/\/mostlymental.com\/index.php?rest_route=\/wp\/v2\/posts\/259\/revisions"}],"predecessor-version":[{"id":276,"href":"http:\/\/mostlymental.com\/index.php?rest_route=\/wp\/v2\/posts\/259\/revisions\/276"}],"wp:attachment":[{"href":"http:\/\/mostlymental.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=259"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/mostlymental.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=259"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/mostlymental.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=259"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}