Question 946258

Complementary angles  add up to {{{90}}}°.

if one angle is {{{alpha}}} and other angle is {{{beta}}},we have 

{{{alpha+beta=90}}}

and if the measure of angle {{{alpha}}}  is {{{80}}}% of the angle {{{beta}}}, then we have

{{{alpha=0.80beta}}}...substitute in {{{alpha+beta=90}}}

{{{0.80beta+beta=90}}}

{{{1.80beta=90}}}

{{{beta=90/1.80}}}

{{{beta=900/18}}}

{{{highlight(beta=50)}}}

now find {{{alpha}}}


{{{alpha=0.80beta}}}

{{{alpha=0.80*50}}}

{{{highlight(alpha=40)}}}