a^2 = 3b^2. If 6b = 18, what is 2a^2?

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BTGModeratorVI wrote:
Mon Sep 14, 2020 8:46 am
a^2 = 3b^2. If 6b = 18, what is 2a^2?

A. 18
B. 54
C. 72
D. 108
E. 162

Answer: B
Source: Veritas Prep
Given: 6b = 18
So, b = 3

Given: a² = 3b²
So, 2a² = 2(3b²) = 6b²
Replace b with 3 to get: 2a² = 6(3²) = 6(9) = 54

Answer: B
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