document.write( "Question 167656: In a certain triangle the measure of one angle is double the measure of a second angle, but is five degress less than the measure of the third angle. If the sum of the measures of the 3 interior angles is always 180 form an algebraic equation to express the problem?\r
\n" ); document.write( "\n" ); document.write( "I came up with a+2a-5=180, but this just doesn't seem right to me, could you please help? Thank you.
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Algebra.Com's Answer #123560 by partygirl1122(6)\"\" \"About 
You can put this solution on YOUR website!
let the angles of the triangle be k, m, and r.
\n" ); document.write( "let k = 2*m
\n" ); document.write( "let k = c-r
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\n" ); document.write( "if k = 2*m, then m = k/2
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\n" ); document.write( "if k = r-5, then r = k+5
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\n" ); document.write( "since the sum of the interior angles of a triangle = 180 degrees, then
\n" ); document.write( "k + m + r = 180
\n" ); document.write( "substituting k/2 for m, and k+5 for r, we get:
\n" ); document.write( "k + k/2 + k + 5 = 180
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\n" ); document.write( "combining like terms, we get:
\n" ); document.write( "2*k + k/2 + 5 = 180
\n" ); document.write( "subtracting 5 from both side of the equation we get:
\n" ); document.write( "2*k + k/2 = 175
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\n" ); document.write( "since 2*k is the same as 4*k/2, we can substitute to get:
\n" ); document.write( "4*k/2 + k/2 = 175
\n" ); document.write( "since the denominators on the left hand side of the equation are the same, this equation becomes:
\n" ); document.write( "(4*k + k)/2 = 175
\n" ); document.write( "which becomes:
\n" ); document.write( "(5*k)/2 = 175
\n" ); document.write( "-----
\n" ); document.write( "multiplying both sides of the equation by 2 gets:
\n" ); document.write( "5*k = 350
\n" ); document.write( "dividing both sides of the equation by 5 gets:
\n" ); document.write( "k = 70
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\n" ); document.write( "k = 70
\n" ); document.write( "m = k/2 = 35
\n" ); document.write( "r = k+5 = 75
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\n" ); document.write( "70 + 35 + 75 = 180
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\n" ); document.write( "algebraic expression to solve the problem was derived above.
\n" ); document.write( "it started off as
\n" ); document.write( "k+m+r = 180
\n" ); document.write( "we solved for m in terms of k.
\n" ); document.write( "we solved for r in terms of k.
\n" ); document.write( "equation became:
\n" ); document.write( "k + (k/2) + (k+5) = 180
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\n" ); document.write( "the rest was simplification to come up with k = 70.
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