542 /www/nrich/html/content/97/12/six3/ 1 2011-02-01T00:00:01 <?xml version="1.0" encoding="UTF-8"?> <mdoxml version="1.0">Determine the total area of the two kissing triangles shaded red.<br></br> <br></br> <div style="text-align: center;"><mdo:image src="kissingsquares.png"></mdo:image></div> <br></br> Is there more than one way of drawing the shape?</mdoxml> <?xml version="1.0" encoding="UTF-8"?> <mdoxml version="1.0"><br></br> <p><span class="editorial">The solution is 18 square centimetres and everyone who submitted a response got it right.</span> <strong><em class="editorial" style="font-style: normal;">Of special mention was the work of Sarah at Hethersett High School and Bryony with Sarah from Maidstone Girls&#39; Grammar, all of whom had painstakingly set out their solutions complete with annotations and diagrams.</em></strong><br></br> <br></br> <em class="editorial" style="font-style: normal;">Some people managed to spot that it there are multiple ways of drawing the shape; the point in the middle where the triangles &#39;kiss&#39; can be moved left or right! Well done to those who realised that despite the variety of ways of drawing the shape, the area is always 18 cm². <strong>Brilliant!</strong></em></p></mdoxml> <?xml version="1.0" encoding="UTF-8"?> <mdoxml version="1.0">Try drawing a diagram of the shape for yourself, making sure it&#39;s to scale. See if you can find the area of some parts of the shape first.<br></br> <br></br> You may wish to use <a href="http://www.geogebra.org">GeoGebra</a> to investigate the shape further.</mdoxml> 2 4 0 0 1 0 0 Determine the total shaded area of the 'kissing triangles'. Measures and Mensuration Area 2D Geometry, Shape and Space Mixed triangles