Systems of Equations via Elimination

3x + 5y = 46
4x + 3y = 43 
x=_____
y=_____

• (7,5)

• (8,2)

• (-9,-2)

• (0,50)

Work Must be shown:

Solve the system by elimination.   −8x − 10y = 20 −8x − 6y = −4 

• Infinite number of solutions  

• (6, 5) 

• (−6, −5) 

• (5, −6) 

Solve the system of equations using elimination.

• f = -2, g = 1

• f = -1, g = 2

• f = 1, g = -2

• f = 2, g = -1

7x - y = 10

-7x + y = -14

• No Solution

• (4, 1)

• Infinitely Many Solutions

• (2, -4)

Answer explanation

7x - y = 10

-7x + y = -14

All of the like terms have opposite coefficients, so both variables will be eliminated when we add the equations together. We cannot eliminate one without the other.

We are left with:

0=-4

This is a contradiction (false), so there is NO SOLUTION.

What is the resulting combined equation for the system below?

• -18x = 18

• y = 18

• 2y= 18

• 18x + 2y = 18

-3x+3y = 18
5x-3y = -26
answers in (x,y)

• (4,2)

• (-4,-2)

• (-4,2)

• (4,-2)

Select the best choice.

• 1

• 2

• 3

• 4

Work Must be shown:

Solve the system by elimination.   −8x − 10y = 20 −8x − 6y = −4 

• Infinite number of solutions  

• (6, 5) 

• (−6, −5) 

• (5, −6) 

What is the solution?

• (1, -2)

• (-2, 1)

• (-4, 1)

• (2, 1)