Question 1049016
let {{{a}}} stand for amount invested at {{{5%}}} then {{{2000-a}}} paid {{{6%}}}

{{{interest}}}+{{{interest}}}={{{interest}}}


{{{5%}}}{{{a}}}+{{{6%}}}({{{20000-a}}})={{{1170}}}
{{{0.05}}}{{{a}}}+{{{0.06}}}({{{20000-a}}})={{{1170}}}
{{{5}}}{{{a}}}+{{{6}}}({{{20000-a}}})={{{117000}}}
{{{5}}}{{{a}}}+({{{120000-6a}}})={{{117000}}}
{{{12000-a}}}={{{117000}}}
{{{-a}}}={{{117000}}}-{{{120000}}}
{{{-a}}}={{{117000}}}-{{{120000}}}
{{{-a}}}={{{-3000}}}
{{{a}}}={{{3000}}}

you solve for {{{a}}}

{{{3000}}} at {{{5%}}} and {{{20000-3000}}} 
which means {{{17000}}} at {{{6%}}}


*[invoke explain_simplification "5a+120000-6a=117000" ]