Question

10) Choose the solution for each linear system.

Answer 1

Answer:

10.  C. (2, -1)

11.  B. (-2, -4)

Step-by-step explanation:

10.

$\left \{ {{x-2y=4} \atop {4x+2y+6}} \right.$

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.

$\left \{ {{6x-2y=-4} \atop {-4x+3y=-4}} \right.$

In order to get terms to cancel out, multiply the top by 3 and bottom by 2

$\left \{ {{18x-6y=-12} \atop {-8x+6y=-8}} \right.$

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)