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3|x-4|+5=9x-7 solve the following equation

User Martis
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1 Answer

14 votes
14 votes

Answer:

x = 2

Explanation:

3|x - 4| + 5 = 9x - 7

3|x - 4| = 9x - 12

|x - 4| = 3x - 4

x - 4 = 3x - 4 or -(x - 4) = 3x - 4

-2x = 0 or -x + 4 = 3x - 4

x = 0 or -4x = -8

x = 0 or x = 2

Check:

x = 0

3|0 - 4| + 5 = 9(0) - 7

12 + 5 = -7

17 = -7

Since 17 = -7 is false, x = 0 is not a valid solution.

x = 2

3|2 - 4| + 5 = 9(2) - 7

6 + 5 = 18 - 7

11 = 11

Since 11 = 11 is true, x = 2 is a valid solution.

Answer: x = 2

User Raffaello
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