The vertex of a parabola is in the first quadrant of a coordinate grid. A line with a negative slope passes through the origin. If the parabola and line intersect at the origin, which statement must be true?

For a vertical parabola, an upward-opening parabola has its vertex as its lowest point. Since the vertex is in the first quadrant, its y-coordinate is positive, so the parabola would stay above the x-axis and could not pass through the origin. Therefore it must open downward; the line’s negative slope does not change this.

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