The slope-intercept form:
y = mx + b
m - slope
b - y-intercept
The parallel lines have the same slope.
We have y = -3x + 7 → m = -3. Therefore y = -3x + b.
Put the coordinates of the point (2, -4) to the equation of a line:
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add 6 to both sides
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Answer: y = -3x + 2