Question 894231
{{{A+S=180}}} Definition of supplementary
{{{A+C=90}}} Definition of complementary
Subtract second equation from first,
{{{A+S-A-C=180-90}}}
{{{S-C=90}}}
Also,
{{{S=4+2C}}}
Substitute,
{{{(4+2C)-C=90}}}
{{{4+C=90}}}
{{{C=86}}}degrees
Then,
{{{A+86=90}}}
{{{A=4}}}degrees