Question 1121918
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<pre>
Let x be the angle measure.


Then the supplement angle is 180 - x degrees.


The condition says


    x = 3*(180-x) - 12.


Simplify and solve for x.


    x = 540 -3x - 12


    4x = 528  ====>   x = {{{528/4}}} = 132 degrees.


<U>Answer</U>.  The angle is 132 degrees.
</pre>

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&nbsp;&nbsp;&nbsp;&nbsp;- <A HREF=http://www.algebra.com/algebra/homework/Angles/Angles-basics.lesson>Angles basics</A> 

&nbsp;&nbsp;&nbsp;&nbsp;- <A HREF=http://www.algebra.com/algebra/homework/Angles/Vertical-Angles-.lesson>Vertical angles</A> 

&nbsp;&nbsp;&nbsp;&nbsp;- <A HREF=https://www.algebra.com/algebra/homework/word/geometry/How-to-solve-problems-on-suppl-compl-or-vertical-angles-Examples.lesson>HOW TO solve problems on supplementary, complementary or vertical angles - Examples</A>

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