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Write an equation in point-slope form of the line that passes through the point (-9,1) and has a slope of 2/3

User Nomaam
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1 Answer

3 votes

Answer:

y - 1 = 2/3(x + 9)

Explanation:

Point slope formula:

y - y1 = m(x - x1)

y1 and x1 represent a set of coordinates and m represents the slope.

If we are given a slope and a points, all we have to do is plug those values into the formula.

We are given:

Point = (-9, 1)

Slope = 2/3

Now that we know the values of each variable in the equation, all we need to do is substitute the values we are given into the formula/equation.

Formula:

y - y1 = m(x - x1)

Substitute:

y - (1) = (2/3)(x - (-9))

Don't get confused by the parenthesis, I only put them there to delineate that I substituted values.

Now simplify a little further while keeping them in their main positions- DO NOT get rid of the parenthesis that are in the original formula (this would atrophy the purpose of the point-slope formula). When we simplify, I mean to combine any negatives/positives (two negatives = positive, two positives = positive, one negative and a positive = negative).

So we get:

y - 1 = 2/3(x + 9)

I added 9 in the parenthesis because two negatives combine to make a positive.

So essentially your equation will be:

y - 1 = 2/3(x + 9)

User Brachamul
by
7.6k points