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Need help urgent! Write an equation y=mx+b just given a line. Picture listed below

Need help urgent! Write an equation y=mx+b just given a line. Picture listed below-example-1

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Answer: y = 1x - 1

Step-by-step explanation: To make the equation using y = mx +b, we need to find the slope of the line and the y intercept (the y value of the graph when the line goes through the y axis).

To find the slope (m), we need to calculate the rise over run or the change in y over the change in x value. Because it is a straight line, the slope is the same throughout the line. Let's choose two points: (2,1) and (-2,-3). Now we use the formula:

Δy/Δx or (y2 - y1)/(x2 - x1)

In this case y2 = 1, x2 = 2, y1 = -3, and x1=-2

Plug in the values in the equation to give...

(1 - (-3)) / (2 - (-2)) = 4/4 = 1

Thus the slope is 1.

This makes sense since the line increases 1 block of height for every 1 block is travels horizontally.

Next, you will need the y-intercept which is -1 because the line intercept the y axis at the value of -1 so the b value is -1.

Finally, plug the values into the y=mx+b to get

y = 1x - 1 or y = x - 1

(x and 1x are the same thing)

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