8th Grade Math Testlet #2 - Slope-Intercept Form

A taxi charges $5.00 plus $0.75 per mile for a ride.

Which equation could be used to represent the total cost, c, in dollars, for a taxi ride of m miles?

• c = 4.25m

• c = 5.75m

• c = 0.75m + 5

• c = 5m + 0.75

Answer explanation

The taxi fee is $5.00 which is your y-intercept. Each mile costs $0.75, so that is your slope.

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CCSS.8.EE.B.5

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What is the equation of the line that passes through the points (0, 5) and (10, 1)?

• y = -2/5x + 5

• y = -5/2x + 5

• y = -2/5x - 5

• y = -5/2x - 5

Answer explanation

Slope is calculated by dividing rise over run.

Calculate the change in y (y2-y1) divided by the change in x (x2-x1).

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CCSS.8.EE.B.6

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A table of values is shown.

Which equation represents the table of values?

• y = 4x – 18

• y = 4x + 46

• y = 1/4x +12

• y = 1/4x +16

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CCSS.8.EE.B.6

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Graham draws a straight line through the points (5, 0) and (0, 4).

Which equation represents Graham’s line?

• y = 4/5x + 4

• y = -4/5x + 4

• y = 5/4x + 5

• y = -5/4x + 5

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CCSS.8.EE.B.6

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Juan is ordering T-shirts. The table shows the cost for ordering different numbers of T-shirts.

Write an equation in slope-intercept form that Juan can use to model the cost, y, of ordering x T-shirts

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Write an equation in slope-intercept form for a line with a slope of –3 and a y-intercept of 5.

• y = -3x + 5

• y = 5x -3

• y = -3x - 5

• y = -5x -3

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CCSS.8.EE.B.6

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Bryan is training for a race. The table shows how many miles he runs each day.

Write an equation that can be used to determine the number of miles, y, Bryan runs on day x.

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CCSS.8.EE.B.6

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