document.write( "Question 72825: set up and splve in a triangle the measure of the first angle is twice the measure of the second angle. The measure of the third angle is 20 degrees less than the second angle. What us the measure of each angle? \n" ); document.write( "

Algebra.Com's Answer #52070 by jim_thompson5910(35256) $\"\"$ $\"About$

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Let f=first angle, s=second angle, t=third angle
\n" ); document.write( " $\"f=2s\"$ the measure of the first angle is twice the measure of the second angle
\n" ); document.write( " $\"t=s-20\"$ he measure of the third angle is 20 degrees less than the second angle
\n" ); document.write( " $\"f%2Bs%2Bt=180\"$ The sum of all of the angles in a triangle equal 180 degrees
\n" ); document.write( "

\n" ); document.write( "Plug in f=2s into f and plug in t=s-20 into t of $\"f%2Bs%2Bt=180\"$
\n" ); document.write( " $\"highlight%282s%29%2Bs%2Bhighlight%28s-20%29=180\"$ Notice how I substituted to have only one variable in the equation
\n" ); document.write( " $\"2s%2Bs%2Bs-20=180\"$ solve for s
\n" ); document.write( " $\"4s-20=180\"$ Add like terms
\n" ); document.write( " $\"4s=200\"$
\n" ); document.write( " $\"s=50\"$
\n" ); document.write( "Plug s=50 into f=2s
\n" ); document.write( " $\"f=2%2850%29\"$
\n" ); document.write( " $\"f=100\"$
\n" ); document.write( "Plug s=50 into t=s-20
\n" ); document.write( " $\"t=50-20\"$
\n" ); document.write( " $\"t=30\"$
\n" ); document.write( "So the 1st angle is 100 degrees, the 2nd angle is 50 degrees, and the 3rd angle is 30 degrees
\n" ); document.write( "Check:
\n" ); document.write( " $\"100%2B50%2B30=180\"$
\n" ); document.write( " $\"180=180\"$ Works \n" ); document.write( "

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