Question

Y=-3x - 4 y= 2x + 1

Answer 1

$\left \{ {{y=-3x-4} \atop {y=2x+1}} \right. \\\\ substitution\ method\\\\ -3x-4=2x+1\ \ \ | subtract\ 2x\\\\ -5x-4=1\ \ \ | add\ 4\\\\ -5x=5\ \ \ | divide\ by\ -5\\\\ x=-1\\\\ y=2x+1=2*(-1)+1=-2+1=-1\\\\ Solution:\\ \left \{ {{y=-1} \atop {x=-1}} \right.$