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Write the point slope form of the equation of the line through the given points: (-4,-1) and (-3,1)

PLEASE EXPLAIN. STEP BY STEP INSTRUCTIONS

Write the point slope form of the equation of the line through the given points: (-4,-1) and-example-1
User Researcher
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Explanation:

the general point-slope form is

y - y1 = m(x - x1)

with (x1, y1) being a point on the line, and m being the slope (the incline of the line).

we have the point. we can pick one from the 2 choices, I typical go for the one with smaller values. so, I will use (-3, 1).

now we need to calculate the slope.

the slope is the ratio "y coordinate change / x coordinate change" when going from one point on the line to another.

so, for our 2 points we see

x changes by +1 (from -4 to -3).

y changes by +2 (from -1 to +1).

and the slope is +2/+1 = 2

therefore our equation is

y - 1 = 2(x - -3)

or simplified

y - 1 = 2(x + 3)

User Rednuht
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