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If a line has a positive slope, what can be said of the angle it makes with the positive đť‘Ą-axis?
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A positive slope means the line is increasing from left to right.
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Now it canâ€™t tilt; it canâ€™t move.
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However, if the line goes directly vertical up and down, itâ€™s considered an undefined slope.
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Or, if it were horizontal, it would be zero slope.
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So it has to be somewhere between the vertical line and the horizontal line.
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This means the angle that would be formed between the positive slope and the positive đť‘Ą-axis is that â€” it must be an acute angle.
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It must be less than ninety degrees.
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Because like we said, it has to be between the undefined slope and the zero slope.
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So it has to stay essentially with the ninety degrees.
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So it canâ€™t be exactly ninety degrees because that would be the up and down undefined slope, and it couldnâ€™t be zero degrees because thatâ€™s a zero slope.
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So if we need a positive slope, then it needs to stay between those.
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So it must be an acute angle, which is between zero and ninety degrees.