Question 755395
System:{{{highlight(x+y=35)}}} and {{{highlight((60x+90y)/35=72)}}}


Maybe continue like {{{60x+90y=35*72}}}, {{{y=35-x}}}
{{{60x+90(35-x)=35*72}}}
{{{6x+90*35-90x=35*72}}}
{{{6x-90x=35*72-90*35}}}
{{{(90-6)x=(90-72)35}}}
{{{86x=18*35}}}
{{{highlight(x=9*35/43)}}}
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and you know what else to do to continue
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