Find the equation of the linear function represented by the table

Find the equation of the linear function represented by the table below in slope-intercept form.
x  y
1  -1
2  -3
3  -5
4  -7

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Slope-intercept form is y = mx + b
m is the slope
b is the y-intercept

Choose two points and find the slope of the line.

(4,-7) and (3,-5) are two points

change in y
------------ = slope
change in x

-5 - (-7)
--------- = slope
3 - 4

2
-- = slope
-1

slope = -2

Substitute one of the points, along with the slope, into slope-intercept form to get the y-intercept.

slope is 2 and point is (3,-5)  {any point will work}
y = mx + b  {slope-intercept form}
-5 = -2(3) + b  {substituted -5 for y, -2 for m, and 3 for x}
-5 = -6 + b  {multiplied 2 by 3}
b = 1  {add 6 to each side}
y-intercept = 1

Substitute slope and y-intercept into slope-intercept form.

y = mx + b  {slope-intercept form}
y = -2x + 1  {substituted}

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