Praxis 5003 Practice Test Practice Question
2x^4 - 3x^3 + 2x - 8 What is the value of the expression shown when x=-3?
Correct Answer: A
Rationale: To find the value of the expression \(2x^4 - 3x^3 + 2x - 8\) at \(x = -3\), substitute \(-3\) into the equation:
1. Calculate \(2(-3)^4 = 2 \cdot 81 = 162\).
2. Calculate \(-3(-3)^3 = -3 \cdot (-27) = 81\).
3. Calculate \(2(-3) = -6\).
4. Combine these results: \(162 + 81 - 6 - 8 = 229\).
Thus, the expression evaluates to 229, confirming that option A is indeed correct.
Options B (−95), C (67), and D (229) do not yield the correct calculations based on substituting \(-3\) into the polynomial, leading to erroneous results.
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