Question 1175130


let Spencer ‘s age be {{{S}}} and Jasmine's age {{{J}}}

if the sum of the ages of Spencer and Jasmine is {{{91}}} years, we have

{{{S+J=91}}}....solve for {{{S}}}

{{{S=91-J}}}....eq.1

 if  {{{8}}} years ago Spencer's age was {{{4}}} times Jasmine's age, we have

{{{S-8=4(J-8)}}}....eq.2......substitute {{{S}}}
{{{91-J-8=4J-32}}}
{{{83-J=4J-32}}}
{{{83+32=4J+J}}}
{{{115=5J}}}
{{{J=115/5}}}
{{{J=23}}}

go to

{{{S=91-J}}}....eq.1....substitute {{{J}}}
{{{S=91-23}}}
{{{S=68}}}

answer: Spencer  is {{{68}}} years old now