Question 895372
By the definition of complementary,
{{{A+C=90}}}
Then also,
{{{A=3C}}}
Substitute,
{{{3C+C=90}}}
{{{4C=90}}}
{{{C=90/4}}}
{{{C=45/2}}}
Then,
{{{A=3(45/2)}}}
{{{A=135/2}}}