Question 1028437
{{{A+S=180}}}
{{{S=3A}}}
Substituting,
{{{A+3A=180}}}
{{{4A=180}}}
{{{A=45}}}
{{{S=3(45)}}}
{{{S=135}}}
.
.
.
{{{A+C=90}}}
{{{C=4A}}}
{{{A+4A=90}}}
{{{5A=90}}}
I'll leave it to you to solve for A and then C.