Question

Difficulty: EasyRational and Radical Expressions and Equations

If 3x2=4\sqrt{3x - 2} = 4, what is the value of xx?

Answer: 6

Answer

The value of xx is 6.
Squaring both sides of the equation 3x2=4\sqrt{3x - 2} = 4 eliminates the radical, leading to 3x2=163x - 2 = 16. Adding 2 to both sides results in 3x=183x = 18. Dividing both sides by 3 gives x=6x = 6. Substituting 6 back into the original equation yields 3(6)2=182=16=4\sqrt{3(6) - 2} = \sqrt{18 - 2} = \sqrt{16} = 4, which verifies that the solution is correct.

Step-by-Step Solution

1
Square both sides of the equation to remove the radical.
3x2=163x - 2 = 16
Squaring a square root removes the radical sign since (a)2=a(\sqrt{a})^2 = a for non-negative values.
2
Add 2 to both sides of the equation.
3x=183x = 18
Adding the constant term moves it to the other side to isolate the term containing the variable.
3
Divide both sides by 3.
x=6x = 6
Dividing by the coefficient of xx yields the final solution.

Key Concept

Solving basic radical equations by isolating the radical and squaring both sides.
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