2018-09-30 23:01:58 +01:00
										 
									 
								 
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								id: 5900f4751000cf542c50ff87
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								challengeType: 5
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								title: 'Problem 264: Triangle Centres'
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											2019-08-05 09:17:33 -07:00
										 
									 
								 
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								forumTopicId: 301913
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											2018-09-30 23:01:58 +01:00
										 
									 
								 
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								---
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								## Description
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								<section id='description'>
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								Consider all the triangles having:
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								All their vertices on lattice points.
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								Circumcentre at the origin O.
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								Orthocentre at the point H(5, 0).
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								There are nine such triangles having a perimeter ≤ 50.
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								Listed and shown in ascending order of their perimeter, they are:
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								A(-4, 3), B(5, 0), C(4, -3)
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								A(4, 3), B(5, 0), C(-4, -3)
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								A(-3, 4), B(5, 0), C(3, -4)
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								A(3, 4), B(5, 0), C(-3, -4)
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								A(0, 5), B(5, 0), C(0, -5)
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								A(1, 8), B(8, -1), C(-4, -7)
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								A(8, 1), B(1, -8), C(-4, 7)
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								A(2, 9), B(9, -2), C(-6, -7)
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								A(9, 2), B(2, -9), C(-6, 7)
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								The sum of their perimeters, rounded to four decimal places, is 291.0089.
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								Find all such triangles with a perimeter ≤ 105.
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								Enter as your answer the sum of their perimeters rounded to four decimal places.
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								</section>
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								## Instructions
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								<section id='instructions'>
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								</section>
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								## Tests
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								<section id='tests'>
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								```yml
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											2018-10-04 14:37:37 +01:00
										 
									 
								 
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								tests:
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								  - text: <code>euler264()</code> should return 2816417.1055.
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											2019-07-26 19:30:17 -07:00
										 
									 
								 
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								    testString: assert.strictEqual(euler264(), 2816417.1055);
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											2018-09-30 23:01:58 +01:00
										 
									 
								 
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								```
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								</section>
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								## Challenge Seed
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								<section id='challengeSeed'>
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								<div id='js-seed'>
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								```js
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								function euler264() {
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											2020-09-15 09:57:40 -07:00
										 
									 
								 
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								  return true;
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								}
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								euler264();
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								```
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								</div>
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								</section>
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								## Solution
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								<section id='solution'>
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								```js
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								// solution required
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								```
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											2019-07-18 08:24:12 -07:00
										 
									 
								 
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											2018-09-30 23:01:58 +01:00
										 
									 
								 
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								</section>
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