Answer:
5. -3, -2/3
Step-by-step explanation:
5.
6x-4y=18
-x-6y=7 multiply this equation by 6 both sides
6x-4y=18
-6x-36y=42 add both equations
-4y-36y=18+42 combine like terms
-40y=60 so y = -4/6= -2/3
subtitute y=-2/3 in -x-6y=7
-x-6*(-2)/3=7 solve
-x+4=7 subtract 4 from both sides
-x=7-4
x= -3
8.
substitute y=4x+5 in to the second equation
12x-3(4x+5)=9
12x-12x-15=9
-15=9 is never true so the equation has no solutions
