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How do you write the equation in slope intercept form given (2,2) and (0,-2)?

User Dkl
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1 Answer

4 votes

Answer:

y = 2x - 2

Explanation:

The slope-intercept form of the equation of a line is

y = mx + b

where m is the slope, and b is the y-intercept.

y = mx + b

First we find the slope, m.

slope = (difference in y)/(difference in x)

It does not make a difference which point is first and which point is second in finding the differences, but you must do the x- and y-differences in the same order.

slope = (-2 - 2)/(0 - 2) = -4/(-2) = 2

The slope is 2, so m = 2, and now we have:

y = 2x + b

We need to find the value of b, the y-intercept.

We use one of the given points. Let's use (2, 2). We plug in 2 for x and 2 for y and solve for b.

2 = 2(2) + b

2 = 4 + b

-2 = b

b = -2

Now that we know the y-intercept is -2, we substitute b with -2.

y = 2x + b

y = 2x - 2

Answer: y = 2x - 2

User Metropolis
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