Answer:
Step-by-step explanation:
In order for a line to have no y-intercept, it must be parallel to the y-axis. Its equation will be of the form ...
x = constant.
If the x-intercept is (3, 0), then we must have constant = 3.
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In order for a line to have no x-intercept, it must be parallel to the x-axis. Its equation will be of the form ...
y = constant.
If the y-intercept is (0, -4), then we must have constant = -4.
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The equation of line m is x = 3.
The equation of line n is y = -4.