Day 1- 2 Combined

Unit 2 Day 1 & 2

Unit: Analyzing Linear Inequalities

Algebra I

Identify the slope and y-intercept for equation of the line on the graph below

Do Now

Do Now

Do Now

I can graph two-variable linear inequalities in slope-intercept and standard form.

Learning Target

Key Vocabulary for Linear Inequalities Symbols

Direct Instruction

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Key Vocabulary for Linear Inequalities in Two Variables

Direct Instruction

y = 2x

y > 2x

Step 2: Graph the "y=" line (make it a solid line for y≤ or y≥, and a dashed line for y< or y>)

Step 1: Make sure your inequality is in slope intercept form. (y=mx+b)

Scenario: You are playing the game “Guess My Number.” Here is the clue: The second number ,y, is more than twice the first number. The inequality y > 2x represents this scenario.

How do you graph an inequality in two variables in slope-intercept form?

Direct Instruction

y > 2x

Test Point: (5,4)

Step 3: Substitute a test point that’s not on the boundary line into the inequality to determine the appropriate half plane to shade.

• If the test point makes the inequality true, shade the half plane where the test point is located.
• If the test point makes the inequality false, shade the half plane that does not include the test point.

How do you graph an inequality in two variables in slope-intercept form?

Direct Instruction

Reveal

(5,4)

How do you graph an inequality in two variables in slope-intercept form?

Direct Instruction

Key Vocabulary for Linear Inequalities in Two Variables

Direct Instruction

5x + 2y 39

Scenario: A store sells hardback books at $5 each and paperback books at $2 each. Write an inequality that models this situation if Maria plans to spend less than or equal to $39 at the store.

How do you write an inequality in two variables in standard from?

Direct Instruction

How do you graph an inequality in two variables in standard from?

Direct Instruction

The Science Club sells T-shirts and key chains to raise money. Write and graph the linear inequality that represents the combinations of T-shirts and key chains could they sell to meet or exceed their goal?

Guided Practice

Reflect

How can I graph a two-variable inequality in slope-intercept form and standard form? How can I test if an order pair is a solution to a two-variable inequality?