M8 Lesson 15 Day 1 Substitution

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 the System by Substitution. Use Teacher Example 1 to help.

y = 8

2x + y = 18

• (5, 8)

• (-5, 8)

• (2, 8)

• (-2, 8)

Solve the System of Equations using substitution

Use Teacher Example 1 for help.

x + y = 9

y = 3

• 6,3

• 3,3

• 18,2

• 21,0

Solve the System of Equations using substitution

Use Teacher Example 1 for help.

x = 6

y = 2x - 3

• (6, 6)

• (6, 9)

• (9, 6)

• (9, 9)

Solve the System of Equations using substitution

Use Teacher Example 2 for help.

y=2x

5x - 2y = 3

• (6, 3)

• (1, 2)

• (3, 6)

• (2, 1)

Solve the System of Equations using substitution

Use Teacher Example 2 for help.

• (3, 6)

• (9, 18)

• (2, 4)

• (9, 32)

Solve the System of Equations using substitution

Use Teacher Example 3 for help.

y = 4x + 1

3x + y = 1

• (1,0)

• (0,1)

• (1,4)

• (4,1)

Solve the system using substitution. Use Teacher Example 3 for help

y = -6x + 5

-2x + y = 5

• (1,0)

• (5,0)

• (0,5)

• (4,0)

Solve the System of Equations using substitution

Use Teacher Example 3 for help.

x + 2y = 2

x = -4y + 2

• (0,2)

• (0,0)

• (1,0)

• (2,0)

Solve the System of Equations using substitution

Use Teacher Example 4 for help.

• (6, 31)

• (31, 6)

• (4, 21)

• (6, 11)