You can put this solution on YOUR website! 8x – 4y = -20 multiply by 5
10x – 5y = 35 multiply by -4 & add
40x-20y=-100
-40x+20y=-140
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0x+0x=-240 no unique solution to these 2 equations.
If graphed you'd find that they are parralel lines.
-4y=-8x=-20
y=-8x/-4-20/-4
y=2x+5 (red line)
10x-5y=35
-5y=-10x+35
y=-10x/-5+35/-5
y=2x-7 (green line) (graph 300x200 pixels, x from -6 to 5, y from -10 to 10, of TWO functions 2x +5 and 2x -7).