Graph . Identify the vertex, which way the graph opens, its intercepts, and its range.
Match the equation to vertex form. Comparing with :
so the vertex is . Rewriting as before reading prevents the usual sign mistake.
Determine the direction and steepness from . Because the graph opens downward — an upside-down V — and because the arms have slopes (left of the vertex) and (right of it), the same steepness as the parent .
Build the graph as a sequence of transformations. Starting from : shift left (because is zero at ), reflect across the -axis, then shift down :
Plot a few points either side of the vertex. Using the slope from :
The symmetry about the vertical line is visible in these values, which is a good check that the horizontal shift was applied correctly.
Read off the intercepts and range. The -intercept is , giving the point . For -intercepts you would need , i.e. , which is impossible since an absolute value is never negative — so there are none. The maximum output is at the vertex, so the range is
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