simultaneous Equations by Substitution

Solve the system of equations using substitution:

-4x + 4y = 8

y = -2x - 10

• (-4, -2)

• (12, -34)

• (4, -18)

• (-2, -6)

Tags

CCSS.8.EE.C.8B

CCSS.HSA.REI.C.6

Solve the simultaneous equations by substitution

x+y=5

x-y=1

• x=2, y=3

• x=3, y=2

• x=3, y=-2

• x=-3, y=2

Tags

CCSS.8.EE.C.8B

CCSS.HSA.REI.C.6

Solve the system by substitution:

y = x + 5
4x + y = 20

• (3,8)
• (8,3)
• (0,2)
• (2,0)

Tags

CCSS.8.EE.C.8B

CCSS.HSA.REI.C.6

What is the first step in solving a system by Substitution?

• Make sure both equations are in standard form.
• Make sure at least one equation is solved for one variable.
• Make sure both equations are in slope-intercept form.
• Make sure both equations can be solved.

Tags

CCSS.8.EE.C.8B

CCSS.HSA.REI.C.6

Solve by substitution:
 $2x-3y=-1$ 
  $y=x-1$  

• (3, 4)

• (4, 3)

• (4, 4)

• (3, 3)

Tags

CCSS.8.EE.C.8B

CCSS.HSA.REI.C.6

Solve by substitution:
 $y=-3x+5$ 
  $5x-4y=-3$  

• (1, 2)

• (1, 1)

• (2, 1)

• (2, 2)

Tags

CCSS.8.EE.C.8B

CCSS.HSA.REI.C.6

3x + y = –14

–2x – y = 9

Which method would be best for solving this system?

• Substitution

• Elimination/Matrices

Tags

CCSS.8.EE.C.8B

CCSS.HSA.REI.C.6