Question 177885
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Line Eqn's:
{{{2x+3y=35}}}, EQN 1
{{{5x+4y=7}}}, EQN 2---->{{{y=(-5x+7)/4=-(5/4)x+(7/4)}}}, EQN 3
In EQN 1 we get,
{{{3y=35-2x}}}---->{{{cross(3)y/cross(3)=(35-2x)/3}}}
{{{y=-(2/3)x+(35/3)}}}, EQN 4, subst. in EQN 2:
{{{5x+4((-2/3)x+(35/3))=7}}}
{{{5x-(8/3)x+(140/3)=7}}}
{{{(15x-8x)/3=7-(140/3)}}}
{{{7x/3=(7-140)/3=(21-140/3)}}}
{{{7x/3=-119/3}}}---->{{{7x=cross(3)*(-119/cross(3))}}}
{{{cross(7)x/cross(7)=cross(-119)17/cross(7)}}}
{{{highlight(x=-17)}}} subt. in EQN 3 or EQN 4:
We use EQN 3:
{{{y=-(2/3)(-17)+(35/3)}}}
{{{y=34/3+(35/3)=highlight(69/3=23)}}}
We see the graph:
{{{drawing(400,400,-25,15,-10,27,grid(1),graph(400,400,-25,15,-10,27,-(2/3)x+(35/3),-(5/4)x+(7/4)),blue(circle(-17,23,.25)))}}}----> RED Line, EQN 1; GREEN Line EQN 2 
Thank you,
Jojo</pre>