Question 242365
Multiply the first eq. by 7 and the second by 3 and add them together to get rid of s.
{{{ 7(7r-3s)+3(3r+7s)=3(35)+7(73) }}}
{{{ 49r-21s+9r+21s=245+219 }}}
{{{ 58r=464}}}
{{{ r=8}}}
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{{{7r-3s=35}}}
{{{7(8)-3s=35}}}
{{{56-3s=35}}}
{{{-3s=-21}}}
{{{s=7}}}
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r=8, s=7