1.0Riley Math Educationhttps://rileymath.comJohn Rileyhttps://rileymath.com/index.php/author/john/rich600338<blockquote class="wp-embedded-content" data-secret="KLFX9kn8A9"><a href="https://rileymath.com/index.php/2026/01/03/euclids-elements-book-1-p13/">Euclids Elements Book 1 P13</a></blockquote><iframe sandbox="allow-scripts" security="restricted" src="https://rileymath.com/index.php/2026/01/03/euclids-elements-book-1-p13/embed/#?secret=KLFX9kn8A9" width="600" height="338" title="“Euclids Elements Book 1 P13” — Riley Math Education" data-secret="KLFX9kn8A9" frameborder="0" marginwidth="0" marginheight="0" scrolling="no" class="wp-embedded-content"></iframe><script> /*! This file is auto-generated */ !function(d,l){"use strict";l.querySelector&&d.addEventListener&&"undefined"!=typeof URL&&(d.wp=d.wp||{},d.wp.receiveEmbedMessage||(d.wp.receiveEmbedMessage=function(e){var t=e.data;if((t||t.secret||t.message||t.value)&&!/[^a-zA-Z0-9]/.test(t.secret)){for(var s,r,n,a=l.querySelectorAll('iframe[data-secret="'+t.secret+'"]'),o=l.querySelectorAll('blockquote[data-secret="'+t.secret+'"]'),c=new RegExp("^https?:$","i"),i=0;i<o.length;i++)o[i].style.display="none";for(i=0;i<a.length;i++)s=a[i],e.source===s.contentWindow&&(s.removeAttribute("style"),"height"===t.message?(1e3<(r=parseInt(t.value,10))?r=1e3:~~r<200&&(r=200),s.height=r):"link"===t.message&&(r=new URL(s.getAttribute("src")),n=new URL(t.value),c.test(n.protocol))&&n.host===r.host&&l.activeElement===s&&(d.top.location.href=t.value))}},d.addEventListener("message",d.wp.receiveEmbedMessage,!1),l.addEventListener("DOMContentLoaded",function(){for(var e,t,s=l.querySelectorAll("iframe.wp-embedded-content"),r=0;r<s.length;r++)(t=(e=s[r]).getAttribute("data-secret"))||(t=Math.random().toString(36).substring(2,12),e.src+="#?secret="+t,e.setAttribute("data-secret",t)),e.contentWindow.postMessage({message:"ready",secret:t},"*")},!1)))}(window,document); </script> ºIts been awhile since I have posted.  I have been busy wrapping up things with my teaching career and beginning retirement.  I am now semi-retired.  Even though I am no longer a full time teacher, I have dedicated most of my time to my former high school as a substitute, a math tutor, a music director and a […]https://rileymath.com/wp-content/uploads/2026/01/B1P13F1-300x176.png