Examples with solutions for Equations with Absolute Values: Identifying functions from graphs

Exercise #1

The graph corresponds to

5

Video Solution

Step-by-Step Solution

To solve this problem, we'll conduct the following steps:

  • Step 1: Identify the vertex of the graph shown.
  • Step 2: Compare the vertex to each function given in the choices.
  • Step 3: Select the function whose vertex matches the graph.

Now, let’s work through these steps:

Step 1: The graph shows a vertex at the point (5, 0). This suggests that the graph is the absolute value function centered at x=5 x = 5 .

Step 2: We compare this with each available function:
- x5 |x-5| : This corresponds to a vertex at (5,0) (5, 0) .
- x3 |x-3| would give a vertex at (3,0) (3, 0) .
- x |x| would give a vertex at (0,0) (0, 0) .
- 5x |5x| involves a similar transformation but with varied scaling and zero vertex.

Step 3: Therefore, the function x5 |x-5| perfectly matches the vertex (5, 0) of the graph plotted.

Our analysis confirms that the absolute value function corresponding to the graph is x5 |x-5| .

Answer

x5 |x-5|

Exercise #2

The graph corresponds to

Video Solution

Step-by-Step Solution

To solve this problem, we'll analyze the graph to match it with the provided equations.

  • Step 1: The graph is in a 'V' shape presenting symmetry around the y-axis and has its vertex at the origin.
  • Step 2: The equation that corresponds to this type of graph is the absolute value function y=x y = |x| . Absolute value functions show symmetry around the y-axis and have a vertex where the argument of the absolute value, here xx, equals zero.
  • Step 3: The graph we see perfectly matches an absolute value function, as it does not extend below the x-axis and has the aforementioned symmetrical properties. Therefore, it is represented by the equation y=x y = |x| .

Therefore, the solution to the problem is y=x y = |x| , matching the graph with the choice corresponding to y=x y = |x| .

Answer

y=x y=|x|

Exercise #3

The graph corresponds to

1

Video Solution

Step-by-Step Solution

Let's proceed to identify the correct function corresponding to the graph:

The graph displays a "V" shape, which is a strong indicator of an absolute value function. To identify it, we must find its vertex.

Given the transformation properties of absolute values, the graph equation is of the general form y=xh+k y = \lvert x - h \rvert + k , where (h,k)(h, k) is the vertex.

  • The vertex for the graph is found at (1,0)(1, 0).
  • This means the function template follows y=x1 y = \lvert x - 1 \rvert . This aligns with an x x translation of 1 to the right.

Checking the answer choices given:

  • Choice (1): y=x1 y = x - 1 - This represents a straight line, not an absolute value function.
  • Choice (2): y=x+1 y = x + 1 - Incorrect due to the vertex position.
  • Choice (3): y=1x y = |1x| - Incorrect due to no translation present: the vertex is unaffected by modifying the coefficient of x x .
  • Choice (4): y=x1 y = \lvert x - 1 \rvert - Matches the (1,0) (1, 0) vertex position and absolute value function type.

Thus, the correct answer is y=x1 y = \lvert x - 1 \rvert .

Answer

y=x1 y=\lvert x-1\rvert

Exercise #4

The graph corresponds to

3

Video Solution

Step-by-Step Solution

To solve this problem, we'll follow these steps:

  • Step 1: Analyze the graph provided. The graph appears to have a distinct 'V' shape, indicating that at least part of the graph is reflected about the x-axis.
  • Step 2: Recognize that a standard quadratic function f(x)=x23 f(x) = x^2 - 3 would have a vertex at (0, -3) if unaltered. Any sections of this below the x-axis being reflected upwards suggests the graph of an absolute value function.
  • Step 3: Apply the absolute value function: When the function is f(x)=x23 f(x) = |x^2 - 3| , all values of f(x) f(x) which are below the x-axis due to x2 x^2 terms less than 3 are reflected above the x-axis.

We can eliminate any function that does not involve an absolute value or shift consistent with reflected x-intercepts. Comparing with each choice:

  • Choice 1 f(x)=x23 f(x) = x^2 - 3 is incorrect because the graph wouldn't show the V-like reflection above the x-axis.
  • Choice 2 f(x)=x23 f(x) = |x^2 - 3| matches perfectly since this transformation reflects all negative portions of the x23 x^2 - 3 graph above the x-axis as observed.
  • Choice 3 f(x)=x2+3 f(x) = |x^2 + 3| is incorrect as this has no crossing or vertex shifts indicating a reflection starting point below the x-axis.
  • Choice 4 f(x)=x2 f(x) = x^2 doesn't reflect along y-values shifted down from 3.

Therefore, the function that corresponds to the graph is f(x)=x23 f(x) = |x^2 - 3| .

Answer

f(x)=x23 f(x)=|x^2-3|

Exercise #5

The graph corresponds to

(3, 2)(3, 2)(3, 2)(7, 2)(7, 2)(7, 2)25

Video Solution

Step-by-Step Solution

We will determine the functions represented by the provided graphs. There are two distinct graphs: a V-shaped graph and a horizontal line. Let's identify each:

1. Observing the V-shaped blue graph, we interpret it as an absolute value function. The shape of such graphs is f(x)=xa f(x) = |x-a| , where the vertex occurs at x=a x = a . The vertex sits at the lowest/highest point, most likely along the line x=5 x = 5 . This suggests f(x)=x5 f(x) = |x-5| .

2. The horizontal red line is a constant function where g(x)=c g(x) = c is consistent across all values of x x . This line crosses at y=2 y = 2 , hence, g(x)=2 g(x) = 2 .

Thus, the functions are:

  • f(x)=x5 f(x) = |x-5|
  • g(x)=2 g(x) = 2

Upon evaluation, these equations best fit the graph representations.

The solution to the problem is f(x)=x5 f(x) = |x-5| and g(x)=2 g(x) = 2 .

Answer

{f(x)=x5g(x)=2 \begin{cases} f(x)=|x-5| \\ g(x)=2 \end{cases}

Exercise #6

The graph corresponds to

(3, 3)(3, 3)(3, 3)(9, 3)(9, 3)(9, 3)36

Video Solution

Step-by-Step Solution

The problem involves determining the equations corresponding to a blue absolute value graph and a red horizontal line based on a given graph.

Firstly, consider the blue absolute value graph:

  • It is symmetric and has a "V" shape, typically expressed as f(x)=xh+k f(x) = |x - h| + k .
  • The vertex, or minimum point, of this graph is at (6, 6). Hence, the equation can be written as f(x)=x6 f(x) = |x - 6| , because at x=6 x = 6 , the function value is at its minimum.
  • The value of k k , the vertical shift, is not explicitly needed here since the vertex already indicates the graph reaches down to the x-axis and f(x)=x6+0 f(x) = |x - 6| + 0 .

Next, assess the red horizontal line:

  • This line crosses the y-axis at y=3 y = 3 , which aligns with the horizontal segment at points (3, 3) and (9, 3).
  • Thus, the constant function equation is g(x)=3 g(x) = 3 .

Upon evaluation of the given choices, choice 1 corresponds correctly with these interpretations:

{f(x)=x6g(x)=3 \begin{cases} f(x)= |x-6| \\ g(x)=3 \end{cases}

Therefore, the correct set of functions is f(x)=x6 f(x) = |x - 6| and g(x)=3 g(x) = 3 .

Answer

{f(x)=x6g(x)=3 \begin{cases} f(x)= |x-6| \\ g(x)=3 \end{cases}

Exercise #7

The graph corresponds to

333-6

Video Solution

Step-by-Step Solution

First, we identify the absolute value function associated with the V-shaped graph. The vertex of this V-shape is at the point (6,0)(-6, 0), indicating an expression of f(x)=x+6 f(x) = |x + 6| .

Next, observe the red horizontal line, which consistently passes through y=3 y = 3 . This confirms that the horizontal line function is g(x)=3 g(x) = 3 .

Having identified both functions, we conclude that they correspond to:

{f(x)=x+6g(x)=3 \begin{cases} f(x)= |x+6| \\ g(x)=3 \end{cases}

Answer

{f(x)=x+6g(x)=3 \begin{cases} f(x)= |x+6| \\ g(x)=3 \end{cases}