Is the slope of Line 1 positive?

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by Ian Stewart » Sat Jun 01, 2019 6:04 am

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Each Statement is clearly insufficient alone. Using both, if line two has a slope of 1, then line two would form a 45 degree angle where it meets any horizontal line. If lines one and two meet at a 40 degree angle, then line one either creates a 5 degree or an 85 degree angle with any horizontal line, but in either case line one would be rising as it moves to the right, so it must have a positive slope, and the answer is C.

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