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Sophia.13
How can you use the vertex and the sign of "a" to determine the range and absolute value of the function?
you can... if a is positive the range is greater than or equal to the y value in the vertex ( this is a minimum at the vertex) if a is negative is will be less than or equal to the y value in the vertex (this is a maximum at the vertex) provided the parabola is in the form y = ax^2 + bx + c