Question 663011


{{{1/x + 3/y = 3/4}}}

{{{3/x - 2/y = 5/12}}}
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{{{(y + 3x)xy= (3/4)}}}

{{{(3y - 2x)xy = (5/12)}}}
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{{{y + 3x= (3/4)xy}}}.....both sides multiply by {{{4}}}

{{{3y - 2x = (5/12)xy}}}....both sides multiply by {{{4}}}
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{{{4y + 12x= 3xy}}}........both sides multiply by 2

{{{36y - 24x = 5xy}}}
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{{{8y + 24x= 6xy}}}

{{{36y - 24x = 5xy}}}
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{{{8y -36y+ 24x- 24x= 6xy-5xy}}}

{{{-24y=xy}}}

{{{-24cross(y)=xcross(y)}}}

{{{highlight(-24=x)}}}

{{{1/-24 + 3/y = 3/4}}}

{{{3/y = 3/4+1/24}}}
 
{{{3/y = 18/24+1/24 }}}

{{{3/y = 19/24}}}
 
{{{3*24 = 19y }}}

{{{72/19 = y}}} 

{{{highlight(3.79 = y) }}}

check:

{{{1/x + 3/y = 3/4}}}

{{{1/-24 + 3/3.79 = 3/4}}}

{{{-0.04+0.79=0.75}}}

{{{0.75=0.75}}}