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Answer:
rules of signs apply
Step-by-step explanation:
The point-slope form of the equation for a line of slope m through point (h, k) is ...
y -k = m(x -h)
If the point coordinates are positive, their values show up in the equation with a minus sign.
Example:
slope 2, point (3, 4)
y -4 = 2(x -3)
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If a point coordinate is negative, its value shows up in the equation with a plus sign.
Example:
slope 2, point (-3, 4)
y -4 = 2(x -(-3)) . . . . fill in the given value
y -4 = 2(x +3) . . . . . simplify according to sign rules
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The slope keeps its sign.
Example:
slope -1/2, point (-3, 4)
y -4 = -1/2(x +3) . . . . we only changed the slope from the previous example
