Question 407761
{{{system(5x-7y=9,4x-3y=33)}}}
Multiply the first equation by 3, the second equation by (-7)
{{{system(15x-21y=27,-28x+21y=-231)}}}
In this way we have the same coefficient, but with different sign, in front of y. If after that we add the first equation to the second equation, the second equation will have only x.
{{{system(15x-21y=27,-28x+15x=-231+27)}}}, {{{system(15x-21y=27,-13x=-204)}}}, {{{system(15x-21y=27,x=204/13)}}}
Put {{{x=204/13}}} in the first equation
{{{system(x=204/13, 15*(204/13)-21y=27)}}}, {{{system(x=204/13, y=129/13)}}}
{{{x}}}=15{{{9/13}}}
{{{y}}}=9{{{12/13}}}