Example

Evaluating the Polynomial Function g(x)=5x2−x−4g(x) = 5x^2 - x - 4

To evaluate the polynomial function g(x)=5x2−x−4g(x) = 5x^2 - x - 4 for specific values, substitute the value for the variable xx and simplify using the order of operations:

  • Evaluate g(−2)g(-2): Substitute −2-2 for xx to obtain g(−2)=5(−2)2−(−2)−4g(-2) = 5(-2)^2 - (-2) - 4. Simplifying the exponent gives 5(4)+2−45(4) + 2 - 4. Multiply to get 20+2−420 + 2 - 4, and simplify to find g(−2)=18g(-2) = 18.
  • Evaluate g(−1)g(-1): Substitute −1-1 for xx to obtain g(−1)=5(−1)2−(−1)−4g(-1) = 5(-1)^2 - (-1) - 4. Simplifying the exponent gives 5(1)+1−45(1) + 1 - 4. Multiply to get 5+1−45 + 1 - 4, and simplify to find g(−1)=2g(-1) = 2.
  • Evaluate g(0)g(0): Substitute 00 for xx to obtain g(0)=5(0)2−0−4g(0) = 5(0)^2 - 0 - 4. Simplifying the exponent gives 5(0)−0−45(0) - 0 - 4, which simplifies to g(0)=−4g(0) = -4.

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Updated 2026-06-03

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