Question 1048892
1.{{{A+S=180}}}
2.{{{A+C=90}}}
and
{{{S=30+5C}}}
Substituting into eq. 1,
{{{A+(30+5C)=180}}}
3.{{{A+5C=150}}}
Subtract eq. 2 from eq. 3,
{{{A+5C-A-C=150-90}}}
{{{4C=60}}}
{{{C=15}}}
So then,
{{{A+15=90}}}
{{{A=75}}}
and
{{{75+S=180}}}
{{{S=105}}}