document.write( "Question 998399: In the triangle, measure of angle 1 + the measure of angle 2+ the measure of angle three equals 180°. If the measure of angle three equals two times the measure of angle one and the measure of angle one equals the measure of angle 2 find the measure of angle three in degrees \n" ); document.write( "
Algebra.Com's Answer #616177 by Theo(13342)\"\" \"About 
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let a = measure of angle 1
\n" ); document.write( "let b = measure of angle 2
\n" ); document.write( "let c = measure of angle 3\r
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\n" ); document.write( "\n" ); document.write( "measure of angle 3 equals 2 times the measure of angle 1.\r
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\n" ); document.write( "\n" ); document.write( "equation for that is c = 2 * a\r
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\n" ); document.write( "\n" ); document.write( "measure of angle 1 equals measure of angle 2.\r
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\n" ); document.write( "\n" ); document.write( "equation for that is a = b\r
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\n" ); document.write( "\n" ); document.write( "sum of the angles is 180 degrees.\r
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\n" ); document.write( "\n" ); document.write( "equation for that is a + b + c = 180\r
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\n" ); document.write( "\n" ); document.write( "you have 3 equations that need to be solved simultaneously.\r
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\n" ); document.write( "\n" ); document.write( "they are:\r
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\n" ); document.write( "\n" ); document.write( "a + b + c = 180
\n" ); document.write( "c = 2 * a
\n" ); document.write( "a = b\r
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\n" ); document.write( "\n" ); document.write( "subce a = b, let's replace b with a in the first equation to get:\r
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\n" ); document.write( "\n" ); document.write( "a + a + c = 180\r
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\n" ); document.write( "\n" ); document.write( "since c = 2 * a, let's replace x with 2 * a in the first equation to get:\r
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\n" ); document.write( "\n" ); document.write( "a + a + 2 * a = 180\r
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\n" ); document.write( "\n" ); document.write( "comtine like terms to get:\r
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\n" ); document.write( "\n" ); document.write( "4 * a = 180\r
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\n" ); document.write( "\n" ); document.write( "divide both sides of this equation by 4 to get:\r
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\n" ); document.write( "\n" ); document.write( "a = 180 / 4 = 45 degrees.\r
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\n" ); document.write( "\n" ); document.write( "since c is equal to 2 * a, then x must be equal to 90 degrees.\r
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\n" ); document.write( "\n" ); document.write( "since a = b, then b must be equal to 45 degrees.\r
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\n" ); document.write( "\n" ); document.write( "we get:\r
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\n" ); document.write( "\n" ); document.write( "a = 45
\n" ); document.write( "b = 45
\n" ); document.write( "c = 90\r
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\n" ); document.write( "\n" ); document.write( "the sum is 280 as it should be.\r
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\n" ); document.write( "\n" ); document.write( "you are asked to find the measure of angle 3 in degrees.\r
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\n" ); document.write( "\n" ); document.write( "since c = measure of angle 3, then angle 3 must be equal to 90 degrees.\r
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\n" ); document.write( "\n" ); document.write( "these solutions satisfy all 3 equations.\r
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\n" ); document.write( "\n" ); document.write( "a + b + c = 45 + 45 + 90 = 180 (good)
\n" ); document.write( "c = 2 * a = 2 * 45 = 90 (good)
\n" ); document.write( "a = b = 45 (good)\r
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\n" ); document.write( "\n" ); document.write( "everything checks out - solution is good.\r
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\n" ); document.write( "\n" ); document.write( "angle 3 is equal to 90 degrees.\r
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