A quadratic function is one of the form f(x) = ax2 + bx + c, where a, b, and c are numbers with a not equal to zero. The graph of a quadratic function is a curve called a parabola. ... A parabola intersects its axis of symmetry at a point called the vertex of the parabola. You know that two points determine a line.
The answer is 10 because 9x5=45 then you do 45-15=30 then you divide by 3 which is 10.
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Answer: The parabola opens upwards.
Step-by-step explanation: