Question

The graph of a quadratic function with vertex (-2,-4) is

Find the domain and the range.

Write the domain and range using interval notation.

Answer 1

Domain: (-∞, ∞); Range: (-∞, -4]

Explanation:

Domain is the set of all possible input values of a function (or on a graph, the leftmost and rightmost extensions of the function).

Since this is a parabola, the function will extend left and right for negative infinity and infinity respectively.

Range is the set of all possible output values of a function (or on a graph, the uppermost and lowermost extensions of the function).

While the function on this graph will extend downward for negative infinity, the uppermost limit is -4, as y (output) value of the vertex.