Answer:
10. C. (2, -1)
11. B. (-2, -4)
Step-by-step explanation:
10.
[tex]\left \{ {{x-2y=4} \atop {4x+2y+6}} \right.[/tex]
The y values cancel out if you add the equations
5x = 10
x = 2
plug in x
2 - 2y = 4
-2y = 2
y=-1
Answer: C. (2, -1)
11.
[tex]\left \{ {{6x-2y=-4} \atop {-4x+3y=-4}} \right.[/tex]
In order to get terms to cancel out, multiply the top by 3 and bottom by 2
[tex]\left \{ {{18x-6y=-12} \atop {-8x+6y=-8}} \right.[/tex]
The y values cancel out if you add the equations
10x = -20
x = -2
plug in x
6(-2) - 2y = -4
-12 - 2y = -4
-2y = 8
y = -4
Answer: B. (-2, -4)
