Question 1114392
{{{system(b=a-40,c=b+2b,a+b+c=180)}}}



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angle c is two times bigger than angle b.
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That is like, if c is p times bigger than b, then  c=b+p.
Best to try avoid confusing with, "if c is p times as big as b, then c=p*b.



{{{system(a=b+40,c=3b,a+b+c=180)}}}

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In a one-variable equation,
{{{(b+40)+b+(3b)=180}}}
.
.
{{{5b=140}}}

{{{highlight(b=28)}}}
and use this to find a and c.