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Find the equation of the line, in slope-intercept form, that passes through the points (-2, -4) and (2,8).A) y = 1/3x + 22/3B) y = 3x + 14C) y = 3x + 2 D) y = - 3x + 14

User OneZero
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1 Answer

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The equation of a line in the slope intercept form is expressed as

y = mx + c

where

m = slope

c = y intercept

The formula for calculating slope is expressed as

m = (y2 - y1)/(x2 - x1)

where

x1 and y1 are the x and y coordinates of the initial point

x2 and y2 are the x and y coordinates of the final point

From the information given, the initial point is (- 2, - 4) and final point is (2, 8)

Thus,

x1 = - 2, y1 = - 4

x2 = 2, y2 = 8

By substituting these values into the slope formula,

m = (8 - - 4)/(2 - - 2) = (8 + 4)/(2 + 2) = 12/4 = 3

We would find the y intercept, c by substituting m = 3, x = - 2 and y = - 4 into the slope intercept equation. We have

- 4 = 3 * - 2 + c

- 4 = - 6 + c

Adding 6 to both sides of the equation,

- 4 + 6 = - 6 + 6 + c

c = 2

By substituting m = 3 and c = 2 into the slope intercept equation, the equation of the line is

C) y = 3x + 2

User Emil Kaminski
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