Unit 2A Test Corrections

Unit 2A Test Corrections

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​Corrections are due by Monday 10/18 @mindnight

Linear Equations

Review for final

Finding slope from ....

• a graph

• a table

• two points

Multiple Choice

Find the slope

• 4/5

• 5/4

• -5/4

• -4/5

Multiple Choice

What is the slope?

• 2/3

• 3/2

• -7

• -5

Find the slope between two points

Multiple Choice

Find the slope of a line that passes through the given points:

(5,1) and (8,3)

• $$\frac{2}{3}$$

• $$\frac{-2}{3}$$

• $$\frac{3}{-2}$$

• $$\frac{3}{2}$$

Multiple Choice

Find the slope of the line that passes through:
(5, -10) and (5, -4)

• undefined
• 0
• - 14/10
• 10/14

Writing Equations in Slope Intercept Form

Multiple Choice

Which equation is being represented by this line?

• y = -x + 2

• y = 1/2x + 2

• y = 3x -4

• y = -3x +2

Multiple Choice

What is the equation of the graph?

• y = -5

• y = 5

• x = -5

• x = 5

Writing linear equation when you have...

• point and slope

• two points

Fill in the Blanks

Write the equation of the line that passes through the point (3,-1) and has a slope of 2

(do not leave any spaces in answer)

Multiple Choice

What is the equation of the line that goes through the points (2, 9) and (3, 1) ?

• y= 8x - 5

• y= -8x + 25

• y= (1/8)x - 2

• y= (-1/8)x + 1

Standard Form : Ax + By = C

• Form is useful to convert to a different form.

• A, B, and C are all whole numbers.

Multiple Choice

Convert the following standard form equation to slope-intercept (y=mx+b).

• 2y = -6x + 24

• y = -3x + 12

Multiple Choice

What is our slope?

y = mx + b

• y

• m

• x

• b

Multiple Choice

What is our y-intercept?

y = mx + b

• y

• m

• x

• b

Multiple Choice

What is the y-intercept in the equation y= -2x + 5

• -2

• 3

• 5

• Cannot be Determined

Multiple Choice

What is the slope in the equation y=2x + 3?

• 2

• 3

• 5

• Cannot be Determined

Multiple Choice

Which is the graph of y=-x+2?

• A

• B

• C

• D

Multiple Choice

Graph. y = 2/3x - 3

• a

• b

• c

• d

Multiple Choice

Which graph is correct for y = ⅖x + 2?

• A

• B

Multiple Choice

Which ordered pair is a solution of the inequality?

y ≥ 4x – 5

• (3, 4)

• (3, 0)

• (2, 1)

• (1, 1)

Graphing Linear Inequalities

• Linear inequalities are graphed the exact same way as linear equations.  You may use the cover-up method to graph when the equation is in Standard Form, Ax + By = C.  Use the y - intercept and slope when equation is in Slope Intercept Form, y = mx + b.

• Some lines will be dotted and some lines will be solid.

• “Greater than” and “Less than” signs ,< and >, will be dotted lines.  This means the line is NOT included in the solution.

• “Greater than or equal to” and “Less than or equal to” signs, ≤ and ≥, will be solid lines.  This means the line IS included in the solution.

  
  

  
  

Graph of a Linear Inequality in Two Variables

The graph of a linear inequality in two variables is the set of all points in the rectangular coordinate system whose ordered pairs satisfy the inequality. When a line is graphed in the coordinate plane, it separates the plane into two regions called half- planes. The line that separates the plane is called the plane divider. 

Consider graphing the solution set of the inequality x + 4y > 12.

Step 3: Shade the appropriate half-plane

Shade the part of the plane divider where the solutions of the inequality is found.

Multiple Choice

$$y<x+3$$  

• right side of the plane divider

• left side of the plane divider

Multiple Choice

$$x≤y–4$$  

• right side of the plane divider

• left side of the plane divider

Multiple Choice

$$2x+y<2$$  

• right side of the plane divider

• left side of the plane divider

Multiple Choice

Select the correct graph for each inequality.

• A
• B
• C
• D

Multiple Choice

Select the correct graph for each inequality.

• A
• B
• C
• D

Multiple Choice

Which of the following equations match the given graph?

• y ≤ -5/4 x + 3
• y ≥ -5/4 x + 3
• y < -5/4 x + 3
• y > -5/4 x + 3

Multiple Choice

For a party, you can spend no more than $12 on peanuts and

cashews. Peanuts are $2.00/lb. and cashews are twice that. Which graph represents the solution set for this situation?