Transforming y=-x^2: Finding the Parabola Negative Everywhere Except at x=-4

Question

Which parabola is the translation of the graph of the function y=x2 y=-x^2

and is negative in all domains except x=4 x=-4 ?

Video Solution

Solution Steps

00:00 Find the correct function according to the data
00:03 We'll use the negative domain, indicating that the parabola opens downward
00:08 Meaning a negative coefficient for X squared
00:12 Let's draw the function based on intersection points and parabola type
00:17 Left shift depends on term P
00:21 We'll substitute in the parabola formula and solve to find the function
00:26 And this is the solution to the question

Step-by-Step Solution

To solve this problem, consider the following steps:

  • Step 1: Recognize that translating a parabola horizontally involves modifying its vertex.
  • Step 2: The original function y=x2 y = -x^2 has its vertex at (0,0) (0, 0) , and it is entirely non-positive.
  • Step 3: To make the parabola non-negative only at x=4 x = -4 , translate this parabola horizontally to have its vertex at (4,0) (-4, 0) .

Let us translate y=x2 y = -x^2 by moving it 4 units to the left, resulting in:

y=(x+4)2 y = -(x + 4)^2

This new equation y=(x+4)2 y = -(x + 4)^2 translates the parabola left by 4 units, positioning the vertex at (4,0) (-4, 0) .

Since the coefficient of (x+4)2 (x + 4)^2 is negative, the parabola is downward opening and is negative anywhere except at its vertex.

Therefore, the translated parabola is indeed negative throughout its domain except at x=4 x = -4 , which satisfies the problem's conditions.

Thus, the parabola is correctly represented by the expression y=(x+4)2\mathbf{y = -(x + 4)^2}.

Answer

y=(x+4)2 y=-(x+4)^2