{"id":4255,"date":"2025-02-01T12:18:28","date_gmt":"2025-02-01T17:18:28","guid":{"rendered":"https:\/\/josmfs.net\/?p=4255"},"modified":"2025-02-01T12:18:28","modified_gmt":"2025-02-01T17:18:28","slug":"chinese-quadrilateral-puzzle","status":"publish","type":"post","link":"https:\/\/josmfs.net\/wordpress\/2025\/02\/01\/chinese-quadrilateral-puzzle\/","title":{"rendered":"Chinese Quadrilateral Puzzle"},"content":{"rendered":"<p><img loading=\"lazy\" decoding=\"async\" class=\"alignleft  wp-image-4252\" src=\"https:\/\/josmfs.net\/wordpress\/wp-content\/uploads\/2025\/02\/Chinese-Quadrilateral-Fig2.jpg\" alt=\"\" width=\"198\" height=\"260\" srcset=\"https:\/\/josmfs.net\/wordpress\/wp-content\/uploads\/2025\/02\/Chinese-Quadrilateral-Fig2.jpg 400w, https:\/\/josmfs.net\/wordpress\/wp-content\/uploads\/2025\/02\/Chinese-Quadrilateral-Fig2-229x300.jpg 229w\" sizes=\"auto, (max-width: 198px) 100vw, 198px\" \/>This is another intimidating <a href=\"https:\/\/mindyourdecisions.com\/blog\/2025\/01\/28\/3-problems-from-china-with-outside-the-box-thinking\/\">puzzle<\/a> from Presh Talwalkar:<\/p>\n<p>\u201cThanks to Eric from Miami for suggesting this problem and sending a solution!<\/p>\n<p>From a 5<sup>th<\/sup> grade Chinese textbook: In the quadrilateral <em>ABCD<\/em>, angle <em>A<\/em> = 90\u00b0, angle <em>ABD<\/em> = 40\u00b0, angle <em>BDC<\/em> = 5\u00b0, angle <em>C<\/em> = 45\u00b0, and the length of <em>AB<\/em> is 6. Find the area of the quadrilateral <em>ABCD<\/em>.\u201d<\/p>\n<p><a href=\"https:\/\/josmfs.net\/wordpress\/wp-content\/uploads\/2025\/02\/Chinese-Quadrilateral-Answer.jpg\">Answer<\/a>.<\/p>\n<p>See the <a href=\"https:\/\/josmfs.net\/wordpress\/wp-content\/uploads\/2025\/02\/Chinese-Quadrilateral-Puzzle-250129.pdf\">Chinese Quadrilateral Puzzle<\/a> for solutions.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>This is another intimidating puzzle from Presh Talwalkar: \u201cThanks to Eric from Miami for suggesting this problem and sending a solution! From a 5th grade Chinese textbook: In the quadrilateral ABCD, angle A = 90\u00b0, angle ABD = 40\u00b0, angle BDC = 5\u00b0, angle C = 45\u00b0, and the length of AB is 6. Find [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[3],"tags":[13,17],"class_list":["post-4255","post","type-post","status-publish","format-standard","hentry","category-puzzles-and-problems","tag-plane-geometry","tag-presh-talwalkar"],"_links":{"self":[{"href":"https:\/\/josmfs.net\/wordpress\/wp-json\/wp\/v2\/posts\/4255","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/josmfs.net\/wordpress\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/josmfs.net\/wordpress\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/josmfs.net\/wordpress\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/josmfs.net\/wordpress\/wp-json\/wp\/v2\/comments?post=4255"}],"version-history":[{"count":1,"href":"https:\/\/josmfs.net\/wordpress\/wp-json\/wp\/v2\/posts\/4255\/revisions"}],"predecessor-version":[{"id":4256,"href":"https:\/\/josmfs.net\/wordpress\/wp-json\/wp\/v2\/posts\/4255\/revisions\/4256"}],"wp:attachment":[{"href":"https:\/\/josmfs.net\/wordpress\/wp-json\/wp\/v2\/media?parent=4255"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/josmfs.net\/wordpress\/wp-json\/wp\/v2\/categories?post=4255"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/josmfs.net\/wordpress\/wp-json\/wp\/v2\/tags?post=4255"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}