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Find the equation of the line passing through the point (2, -4) that is parallel to the line y=3x+2​

1 Answer

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Answer (assuming it can be put in point-slope format):


y + 4 = 3(x-2)

Explanation:

You can write an equation of a line when knowing its slope and a line it passes through using point slope formula,
y-y_1 = m (x-x_1).

1) First, find the slope of the equation. We know it has to be parallel to y = 3x + 2. Lines that are parallel have the same slope, thus the slope of y = 3x + 2 is the slope of the answer as well. y = 3x + 2 is in slope-intercept format, or
y = mx + b. The coefficient of the x term, or
m, represents the slope - so, the slope must be 3.

2) Now, use point-slope formula,
y-y_1 = m (x-x_1), to write the equation. Substitute
m,
x_1, and
y_1 for real values.

The
m represents the slope, so substitute 3 for
m. The
x_1 and
y_1 represent the x and y values of a point the line crosses through. The line crosses through (2, -4), so substitute 2 for
x_1 and -4 for
y_1. This gives the following answer:


y - (-4) = 3 (x-(2))\\y + 4 = 3(x-2)

User Dragos Rusu
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