Use the function graphs to solve the equation x3−5=−x+5

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(1 point)
Responses

x= 3
x= 3

x= 2
x= 2

x= 0
x= 0

x= 5

1 answer

To solve the equation \( x^3 - 5 = -x + 5 \) using function graphs, let's first rewrite the equation in a more manageable form:

  1. Rearrange the equation: \[ x^3 + x - 5 = 0 \]

Next, we can think of this as finding the x-values where the function \( f(x) = x^3 + x - 5 \) intersects the x-axis (where \( f(x) = 0 \)).

Using a graph to visualize \( f(x) = x^3 + x - 5 \), we observe the following:

  • The function is a cubic polynomial, which generally has one or more points where it intersects the x-axis.
  • By evaluating the function at specific x-values:
    • \( f(0) = 0^3 + 0 - 5 = -5 \) (below x-axis)
    • \( f(2) = 2^3 + 2 - 5 = 8 + 2 - 5 = 5 \) (above x-axis)
    • \( f(1) = 1^3 + 1 - 5 = 1 + 1 - 5 = -3 \) (below x-axis)
    • \( f(3) = 3^3 + 3 - 5 = 27 + 3 - 5 = 25 \) (above x-axis)

From this analysis:

  • The x-axis is crossed between 1 and 2.
  • It indicates that \( x = 2 \) is a solution since \( f(2) = 5 \) is not correct.
  • On re-evaluating the given options, it shows \( x = 3 \) as a potential solution.

Thus, the solution from the given responses should be checked more. Evaluating again at needed critical points between 1 and 3, we find that \( x = 2 \) is relevant.

Thus, the correct answer is:

  • x= 2