Is y=2x(x-2) a quadratic function

The graph opens downward, so the vertex is the maximum point of the parabola. Example: The vertex of the parabola y = -(x + 9)2 + 4 is (-9, 4). The graph opens downward, so the vertex is the maximum point of the parabola.
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If the value of "a" is positive, the parabola will open upward.

Your answer would be ahere is how: perimeter is how long all the sides are. in a rectangle, there are two sets of parallel sides. so, to find this, we would to the following.(15x2)+(4x2)30+838if you have questions ask! and mark me brainliest! i really wanna level up : 3

Here are the answers to the ones that i could see.