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24 votes
24 votes
Solve for x

2|x-1|=1/2x+8

User Abhiklpm
by
3.0k points

1 Answer

21 votes
21 votes

Answer:

x = 20/3 or x = -12/5

Explanation:

Solve for x over the real numbers:

2 abs(x - 1) = x/2 + 8

Divide both sides by 2:

abs(x - 1) = 1/2 (x/2 + 8)

Split the equation into two possible cases:

x - 1 = 1/2 (x/2 + 8) or x - 1 = 1/2 (-x/2 - 8)

Expand out terms of the right-hand side:

x - 1 = x/4 + 4 or x - 1 = 1/2 (-x/2 - 8)

Subtract x/4 - 1 from both sides:

(3 x)/4 = 5 or x - 1 = 1/2 (-x/2 - 8)

Multiply both sides by 4/3:

x = 20/3 or x - 1 = 1/2 (-x/2 - 8)

Expand out terms of the right-hand side:

x = 20/3 or x - 1 = -x/4 - 4

Add x/4 + 1 to both sides:

x = 20/3 or (5 x)/4 = -3

Multiply both sides by 4/5:

Answer: x = 20/3 or x = -12/5

User Paco Abato
by
2.5k points