Evaluate 3a² − 2b when a = 4 and b = 5.
Correct answer: D. 38
a² = 16, so 3a² = 48, and 2b = 10. Then 48 − 10 = 38. Square first, then multiply, following the order of operations. Note that 3a² means 3 × (a²), not (3a)², which would be 144.
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Answer and explanation
The correct answer is D. 38
a² = 16, so 3a² = 48, and 2b = 10. Then 48 − 10 = 38. Square first, then multiply, following the order of operations. Note that 3a² means 3 × (a²), not (3a)², which would be 144.
Topic: Algebra and Equations MCQs · Subject: Numerical Ability