6-2 Systems with Substitution

Solve for x and y
y = 2x + 1
y = 4x - 1

• (1,3)
• (-1,-3)
• (-1,3)
• (3,1)

Tags

CCSS.HSA.REI.C.9

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

• (4,1)
• (4,-1)
• (1,4)
• (-1,4)

Tags

CCSS.HSA.REI.C.9

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

• (-1.5,-4)
• (1.5,4)
• No solution (parallel lines)
• Infinitely many solutions

Tags

CCSS.8.EE.C.8B

Use substitution to solve the system of equations.

x - 7y = 11
5x + 4y = -23

• (-3, -2)
• (-4, 1)
• (4, -1)
• (3, 2)

Solve using substitution.
x - 2y = 2
3x + 4y = 3

• (1.4, -0.3)
• (3.1, 5)
• (-2.5, 3.5)
• (6.9, 1.02)

Tags

CCSS.8.EE.C.8B

CCSS.HSA.REI.C.6

Solve using substitution.
2x - 2y = 2
y = -5x + 14

• (4, 5)
• (2.5, 1.5)
• (1.5, 5)
• (1, 2.25)

Tags

CCSS.8.EE.C.8B

CCSS.HSA.REI.C.6

• infinitely many solutions

• one solution

• no solutions

• ( 1, 7)

• ( -3, 3)

• ( -6, -3/2 )

• ( 4, -11)

• ( 3, -3)

• ( 3, -4)

• ( 6, -2)

• ( 4, 6)

If I were to solve for x in the second equation, what would be the only step?

-7x - 2y = (-13)

x - 2y = 11

• Add x

• Subtract 11

• Subtract 2y

• Add 2y

Tags

CCSS.HSA.REI.B.3