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Solve (9x-4)^2=18 using the square root method

User Dave Bish
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1 Answer

4 votes

Answer:

x = 4/9 + sqrt(2)/3 or x = 4/9 - sqrt(2)/3

Explanation:

Solve for x over the real numbers:

(9 x - 4)^2 = 18

Take the square root of both sides:

9 x - 4 = 3 sqrt(2) or 9 x - 4 = -3 sqrt(2)

Add 4 to both sides:

9 x = 4 + 3 sqrt(2) or 9 x - 4 = -3 sqrt(2)

Divide both sides by 9:

x = 4/9 + sqrt(2)/3 or 9 x - 4 = -3 sqrt(2)

Add 4 to both sides:

x = 4/9 + sqrt(2)/3 or 9 x = 4 - 3 sqrt(2)

Divide both sides by 9:

Answer: x = 4/9 + sqrt(2)/3 or x = 4/9 - sqrt(2)/3

User PorssiMies
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4.6k points