Question 1136972
<pre>
first          x
second         y
third          y+18
sentence2      y+(y+18)=2x      
SUM           x+y+(y+18)=180
</pre>


{{{system(2y+18=2x,x+2y+18=180)}}}

-

{{{system(x-y=9,x+2y=162)}}}
{{{E2-E1}}}:
{{{3y=162-9}}}
{{{3y=153}}}
{{{highlight(y=51)}}}
-
{{{y+18=highlight(69)}}}
-
{{{x=9+y}}}
{{{x=9+51}}}
{{{highlight(x=60)}}}


60, 51, 69


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