Question 521574
let's the complement angles be {{{alpha}}} and {{{beta}}}

by definition of complement angles {{{alpha+beta=90}}}


Three times the complement of an angle is 30 degrees less than the angle:

{{{3*beta +30=alpha}}}.... plug it in {{{alpha+beta=90}}} and solve for {{{beta}}}

{{{3*beta +30+beta=90}}}

{{{4*beta =90-30}}}

{{{4*beta =60}}}

{{{beta =60/4}}}

{{{beta =15}}}....now find {{{alpha}}}

{{{alpha=3*beta +30}}}

{{{alpha=3*15 +30}}}

{{{alpha=45 +30}}}

{{{alpha=75}}}