Answer :
[tex] \left \{ {{y=2x+4} \atop {-5x-5y=-5}} \right. \\\\ substitute\ first\ equation\ into \ the\ second\\\\
-5x-5(2x+4)=-5\\\\
-5x-10x-20=-5\\\\
-15x-20=-5\ \ \ | add\ 20\\\\
-15x=15\ \ \ | divide\ by\ -15\\\\
x=-1\\\\
y=2*(-1)+4=-2+4=2[/tex]
y=2x+4
-5x-5y=-5
subsitute 2x+4 for y
-5x-5(2x+4)=-5
-5x-10x-20=-5
-15x-20=-5
add 20 to both sdies
-15x=15
divide by -15
x=-1
subsitute
y=2(-1)+4
y=-2+4
y=2
x=-1
y=2
-5x-5y=-5
subsitute 2x+4 for y
-5x-5(2x+4)=-5
-5x-10x-20=-5
-15x-20=-5
add 20 to both sdies
-15x=15
divide by -15
x=-1
subsitute
y=2(-1)+4
y=-2+4
y=2
x=-1
y=2
