If x > 4 and 3x - 2y = 0, then which of the following must be true?

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3 x - 2y = 0; x>4

=> x = 2/3 (y)

=> (2/3) y > 4
=> y > 6

Answer: E

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BTGModeratorVI wrote:
Thu Jun 11, 2020 8:31 am
If x > 4 and 3x − 2y = 0, then which of the following must be true?

A. y < −6
B. y < −4
C. y = 6
D. y < 6
E. y > 6

Answer: E
Source: Kaplan
Given: 3x − 2y = 0
Add 2y to both sides to get: 3x = 2y
Divide both sides by 3 to get: x = 2y/3

Given: x > 4
Substitute above value of x to get: 2y/3 > 4
Multiply both sides of the inequality by 3 to get: 2y > 12
Divide both sides of the inequality by 2 to get: y > 6

Answer: E

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BTGModeratorVI wrote:
Thu Jun 11, 2020 8:31 am
If x > 4 and 3x − 2y = 0, then which of the following must be true?

A. y < −6
B. y < −4
C. y = 6
D. y < 6
E. y > 6

Answer: E
Solution:

Since 3x > 12 and 3x = 2y, we have:

2y > 12

y > 6

Alternate Solution:

We can let x = 5 and substitute this into the equation, obtaining:

3(5) - 2y = 0

15 = 2y

7.5 = y

Since 7.5 > 6, we can see that only choice E is the correct answer.

Answer: E

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