Answer:
Isiah is correct. The slope is about 0.344.
Step-by-step explanation:
Lyra and Isiah want the slope of the hypotenuse in a triangle with an angle of elevation of 19°.
The slope is the ratio of "rise" to "run". In a right triangle, that is the ratio "opposite"/"adjacent". This ratio is the tangent of the angle of elevation.
tan(19°) ≈ 0.344
The slope is about 0.344. Isiah is correct.
Isiah knows Lyra is not correct because the slope in a triangle with a 45° angle is 1. Lyra' value of 2.675 is about right for an angle of 69.5°, much greater than either 45° or the given angle of 19°.
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Additional comment
Unfortunately, the diagram is not drawn to scale. This is often the case with diagrams in geometry problems. The diagram here is misleading in that it seems to show a slope greater than 1 for a 19° angle.