The equation of the line will be y = -3.9, and the height after rounding off will be -4.
<h3>What is a straight line?</h3>
A straight line is a combination of endless points joined on both sides of the point.
The slope 'm' of any straight line is given by:

The horizontal line can be defined as:
y = a
Where a is the constant.
Here a = -3.9
y = -3.9
The height = -3.9 ≈ -4
Thus, the equation of the line will be y = -3.9, and the height after rounding off will be -4.
Learn more about the straight line here:
brainly.com/question/3493733
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