Hi student, let me help you out! :)
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We are asked to find the equation of the line, using the given information:
, which is the slope
which is a point that the line contains
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- The slope is the number before x, in the form
.
Since "m" is the slope, and we're given what the slope is, we can substitute -3 for m:

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Now, we need to find the y intercept, "b", of the line.
Here's how it's done:
Remember the point that the line contains, (1,2)?
Well, its y-coordinate is 2; so what we do is substitute 2 for y:
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Also, its x-coordinate is 1, so we substitute 1 for x:
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Now, solve for b:
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Add 3 to both sides:

Thus, we have
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Thus, the equation of the line is:
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Hope it helps you out! :D
Ask in comments if any queries arise.
#StudyWithBrainly
~Just a smiley person helping fellow students :)
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