A2_2B_Feb13_Quiz

Identify a possible first step using the elimination method to solve the system and then find the solution to the system.

3x + 2y = 24

6x + 2y = 30

• Multiply second equation by 2, solution (2, 9).

• Multiply first equation by -2, solution (2, 9).

• Multiply second equation by 2, solution (2, -9).

• Multiply first equation by -2, solution (2, -9).

Solve the system of equations.

a + b = 10

a - b = 2

• a = 5, b = 5

• a = 2, b = 8

• a= 6, b = 4

• a = 3, b = 7

If the plan is to add the two equations to solve, what could be the first step to solve this system of equations?

3x - 7y = 10

2x - 5y = 12

• Multiply the first equation by 2 and the second equation by 3.

• Multiply the first equation by 5 and the second equation by 7.

• Multiply the first equation by -2 and the second equation by 3.

• Multiply the first equation by -2 and the second equation by -3.

Marybeth is going to solve this problem by multiplying the top equation by -2. If she does this and combines the equations, what does she get?

3x - 5y = 10

6x + 3y = -6

• -13y = -26

• -7y = 14

• -2y = 4

• 13y = -26

If you were going to solve this equation by substitution, what would your first step look like?

x = 4y - 2

x - 3y = 6

• x - 4y - 2 = 6

• 4y - 2 - 3y = 6

• x - 12y - 6 = 6

• x - 12y + 6 = 6

Identify a possible first step using the elimination method to solve the system and then find the solution to the system.

12x – 3y = 6

2x – y = 2

• Multiply second equation by 6, solution (2, 0).

• Multiply second equation by 6, solution (-2, 0).

• Multiply second equation by -6, solution (0, 2).

• Multiply second equation by -6, solution (0, -2)

If (p, q) is the solution to the system of equations, what is the value of q?

−16p − 2q = 100

p − 4q = 200

• 0

• -10

• -25

• -50

Solve the system by elimination. What is the product of the solution?

−4x − 2y = −12

4x + 8y = −24

• 6

• -6

• 36

• -36

Solve the system by elimination. What is the sum of the solution (x, y)?

4x + 8y = 20

−4x + 2y = −30

• 7

• -7

• 6

• -6

Solve the system by elimination. What is the value of x?

−6x + 6y = 6

−6x + 3y = −12

• 3

• 4

• 5

• 6