Solving Systems of Equations Algebraically

Solve this system using elimination
4x+ 9y = 28
-4x -y = -28

• (-7,0)

• (6,0)

• (-6,0)

• (7,0)

Solve for x and y
5x + 3y = 7
y = 4

• (4,1)

• (4,-1)

• (1,4)

• (-1,4)

Solve:
y = 2x -11
-3y = -6x -15

• (-1.5,-4)

• (1.5,4)

• No solution (parallel lines)

• Infinitely many solutions

4x+8y=20
-4x+2y=-30

• (-7,1)

• (2,-5)

• (-2,5)

• (7,-1)

x-y=11
2x+y=19

• (10,-1)

• (-1,10)

• (3,-4)

• (6,7)

Solve the system of Equation (x,y)
3x + y = –21
x + y = –5  

• (-3,8)

• (8,-3)

• (3,-8)

• (-8,3)

What is the solution?

• One Solution

• No solution

• Infinitely Many Solutions

Erin is 3 years younger than twice Alex's age. Their ages combined are 33 years. How old are Alex and Erin. If x=Erin's age and y=Alex's age, choose the system that matches the situation.

• x + y = 33
  y = 2x - 3

• x + y = 33
  x = 2y - 3

• x + y = 33
  x = 3 - 2y

• x + y = 3
  x = 33 - 2y

What is the value of the y-coordinate of the solution to the system of equations 
x-2y=1
x+4y=7 

• 1

• -1

• 3

• 4

The equations of two lines are:
 2x-y=4 and y=-2x+8.
What is the value of x in the solution for this system?

• x=8

• x=3

• x=11

• x=5