Week 5 – Solving Radical Equations
Consider the equation
To solve the equation, we need to isolate x. Square roots and squaring are inverse operations. So, square both sides of the equation to “undo” the square root.
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Now, we subtract 1 from each side to get rid of the 1 added to the equation. Remember; what you do to one side, you have to do to the other.
To isolate x, divide both sides by 3.
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Check the answer. Substitute x = 8 in the original equation.
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Since the left side equals the right side, the root of the equation is 5.
Restriction:
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or