8th grade Unit 5 Post-Test: Linear Functions

MGSE8.EE.5: Choosing two points from the table.

Which equation matches the function described in the table?

• A. y = x – 4

• B. y = 4x – 1

• C. y = -4x + 1

• D. D. y = -3x – 2

MGSE8.F.2, MGSE8.EE.5, MGSE8.F.3: A reporter collected data on y, the depreciation of a certain car for various years, x, after it had been purchased new. The equation below was fit to the data.

y = 16,500 -1,500x

What is the rate of change (slope) in the above equation?

• A. 16,500

• B. 1,500x

• C. -1,500

• D. -1,500x

What is the equation of this line?

• y= 3x+1

• y= -x+3

• y= 1/3x-1

• y= -1/3x+1

Which of these represents the standard form of a linear equation?

• y₂-y₁/x₂-x₁

• y - y₁ = m(x - x₁)

• Ax + By = C

• y = mx + b

Change the following equation to slope-intercept form:

5x - 5y = 25

• y = x - 5

• y = 5x - 1

• y = -x + 5

• y = 5x + 1

Write the equation in point-slope form of the line that passes through the given point and has the given slope.

(4, -7); m = -1/4

• y + 7 = -1/4(x - 4)

• y - 4 = -1/4(x + 7)

• y + 7 = 4(x - 4)

• y - 7 = -1/4(x - 4)

Change the following equation to slope intercept form:

y + 2 = -3(x - 5)

• y = -3x + 17

• y = -3x + 13

• y = -3x - 13

• y = -3x - 17

Determine the slope and y-intercept from the following equation: y = 3/2x + 3

• slope: 5 y-intercept: (0,3)

• slope: 3/2 y-intercept: (0,3)

• slope: 4 y-intercept: (0,3/2)

• slope: 1/5 y-intercept: (0,5)

Find the slope of the line that passes through:

(6,7) and (4,2)

• 2/5

• -5/2

• 5/2

• -1/2

What is the slope in the picture?

• Positive

• Negative

• Undefined

• Zero