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Help last day !!!!!!!!!!!!!!!

Help last day !!!!!!!!!!!!!!!-example-1

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Answer:

The equation of the lines with the given point does not have a y-intercept of 4 but has a y-intercept of -4.

Explanation:

y-intercept is 4

addition ordered pairs on the line are (2, -2), (4, 0), (6, 2), (8, 4)

Find the slope using two of the points: (2, -2), (4, 0).

Slope = (change in the y values)/(change in the x values0

Slope = [0 -(-2)]/ (4 - 2) = 2/ 2 = 1

Checking to see if the y-intercept is 4 substituting slope (m) = 1 and (2, - 2)

y = mx + b

-2 = 1(2) + b

-2 = 2 + b

-2 - 2 = b

-4 = b so we know that the y-intercept is not 4 but it is -4.

Now write the equation of the line using a slope = 1 and y-intercept of -4

y = mx + b

y = x - 4

Next check the other points into the equation of the line to see if the equation is correct.

x = 2 did y = -2 ? y = x - 4; y = 2 - 4 ; y = -2 point (2, -2) works.

x = 4 did y = 0? y = x - 4; y = 4 - 4; y = 0 point (4,0) works.

x = 6 did y = 2? y = x - 4; y = 6 - 4; y = 2 point (6, 2) works.

x = 8 did y = 4? y = x - 4; y = 8 - 4; y = 4 point (8, 4) works.

User Andrea Gherardi
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