The table shows values for functions $f(x)$ and $g(x)$.

x$f(x)=2^{-x}$$g(x)=-2 x$
-386
-244
-122
010
1$\frac{1}{2}$-2
2$\frac{1}{4}$-4
3$\frac{1}{8}$-6

Verified Answer :

  • Inspect the provided table to compare \(f(x) = 2^{-x}\) and \(g(x) = -2x\) for every given \(x\).
  • Identify rows where the values of \(f(x)\) and \(g(x)\) are identical.
  • Determine the \(x\)-values for these matches as the solutions to the equation \(f(x) = g(x)\).
  • Conclude that the solutions are \(\boxed{-2, -1}\).

Explanation

  1. Analysis of the Given Data

To determine the solutions to the equation \(f(x) = g(x)\), we must find the values of \(x\) for which the outputs of both functions are identical. We are given two functions, \(f(x) = 2^{-x}\) and \(g(x) = -2x\), and a table of their values over the interval \(x \in \{-3, -2, -1, 0, 1, 2, 3\}\). By inspecting the table, we can directly compare the outputs for each \(x\).

  1. Evaluating the Equation at Each Point

We examine the table row by row to find where \(f(x)\) equals \(g(x)\):

  • For \(x = -3\): \(f(-3) = 8\) and \(g(-3) = 6\). Since \(8 eq 6\), this is not a solution.
  • For \(x = -2\): \(f(-2) = 4\) and \(g(-2) = 4\). Since \(4 = 4\), \(x = -2\) is a solution.
  • For \(x = -1\): \(f(-1) = 2\) and \(g(-1) = 2\). Since \(2 = 2\), \(x = -1\) is a solution.
  • For \(x = 0\): \(f(0) = 1\) and \(g(0) = 0\). Since \(1 eq 0\), this is not a solution.
  • For \(x = 1\): \(f(1) = 0.5\) and \(g(1) = -2\). Since \(0.5 eq -2\), this is not a solution.
  • For \(x = 2\): \(f(2) = 0.25\) and \(g(2) = -4\). Since \(0.25 eq -4\), this is not a solution.
  • For \(x = 3\): \(f(3) = 0.125\) and \(g(3) = -6\). Since \(0.125 eq -6\), this is not a solution.
  1. Conclusion

Based on our comparison of the function values in the table, the equation \(f(x) = g(x)\) is satisfied when \(x = -2\) and \(x = -1\). These points represent the intersections of the graphs of \(f(x)\) and \(g(x)\). Thus, the solutions to the equation are \(x = -2\) and \(x = -1\). The final answer is \(\boxed{-2, -1}\).

Examples

Graphing systems of equations is essential in fields like engineering and economics. For example, if you are modeling the profit of a company where one function represents revenue and another represents costs, the point where the two graphs intersect (where revenue equals cost) identifies the "break-even point." Finding these intersections allows decision-makers to determine the production levels needed to achieve profitability or to understand the threshold where one model outperforms another.