Algebra Review: Day 2 (Part B)

Tuesday Independent Practice | North Star Academy

Name: ______________________

Date: ______________________

8.2

Unit 8.2: Solving by Substitution

The Substitution Guide:

1. Find the "lonely variable" (like y = 3x).
2. Plug that value into the other equation.
3. Solve for the missing letter.

1. FOOD: Find the cost of burgers (x) and drinks (y).

y = 3x

Step 1: The Lonely Variable

x + y = 20

Step 2: The Plug-In Eq

Substitution Move:

x + (

) = 20

Work Space to Solve for x:

x = ________

2. MEDIA: Solving for shared monthly cost.

y = 5x + 2

y = 12

Substitution Result:

12 = 5x + 2

Solve for x (Show each step):

x = ________

8.3

Unit 8.3: Solving by Elimination

The Elimination Trick:

Add the equations vertically to DELETE a variable that matches but has an opposite sign (+ and -).

3. SPORTS: Total equipment bill elimination.

2x + y = 10
3x - y = 5

5x + 0 = 15

Final Calculation:

"Divide by 5 on both sides to find x"

x = ________

4. FOOD: Solving for orders.

4x + 2y = 20
-4x + 3y = 5

0 + 5y = 25

Solve for y (Show steps):

y = ________

Tuesday Mastery Review

The Final Case File

Elimination Logic Check:

"What happens to the Y when you add these equations together?"

x + y = 10
x - y = 4

Y is Deleted (0)

X is Deleted (0)

Substitution Calculation:

"If you know x = 5, what is the value of y in y = 2x?"

y = ________

TUESDAY POWER STAMP

Tuesday Algebra Power Review Worksheet

Tuesday Algebra Power Review Worksheet