Question 1152990

supplementary angles are two angles whose sum is {{{180}}}°

let an angle be {{{alpha}}} and other angle {{{beta}}}, then

{{{alpha+beta=180}}}°.........eq.1

if angle {{{alpha}}}  measures {{{78.4}}}° less than the measure of its supplementary angle {{{beta}}}, we have

{{{alpha=beta-78.4}}} .....eq.2..substitute in eq.1

{{{beta-78.4+beta=180}}}°

{{{2beta=180+78.4}}}°

{{{2beta=258.4}}}°

{{{beta=258.4/2}}}°

{{{beta=129.2}}}°


go to eq.2

{{{alpha=beta-78.4}}}° .....eq.2, substitute {{{beta}}}

{{{alpha=129.2-78.4}}}°

{{{alpha=50.8}}}°


so, your angle are: {{{50.8}}}° and {{{129.2}}}°