<PRE><B>Question 111366</B>
{{{5x + 7y = b}}} Start with the first equation



{{{5(-3) + 7(4) = b}}} Plug in x=-3 and y=4. This is the solution (-3,4)



{{{-15+28= b}}} Multiply


{{{13= b}}} Add


So {{{b=13}}}




{{{mx + y = 22}}} Now move onto the next equation



{{{m(-3) + (4) = 22}}} Plug in x=-3 and y=4



{{{-3m+4= 22}}} Multiply


{{{-3m= 18}}} Subtract 4 from both sides



{{{m= -6}}} Divide both sides by -3 to isolate m


So {{{m=-6}}}
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