Solving an Equation with Two Radical Terms
Example
Solve for x:
Solution Step 1 Isolate a radical term.
Subtract
from both sides.
Step 2 Apply the Principle of Powers.
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= 2
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Square both sides. |
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Step 3 Solve the resulting equation.
Write the right side as a product. |
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FOIL the right side.
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Isolate the remaining radical term.
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2x - 6 |
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Divide both sides by 2.
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x - 3 |
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Square both sides.
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(x - 3)2 |
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Write the left side as a product.
Simplify.
Write in standard form.
Factor.
Use the Zero Product Property.
Solve for x. Step 4 Check the solution. |
(x - 3)(x - 3)
x2 - 6x + 9
x2 - 10x - 21
(x - 3)(x - 7)
x - 3 = 0 or x - 7
x = 3 or x |
= 4(x - 3)
= 4x - 12
= 0
= 0
= 0
= 7 |
Since x = 7 does not check, the only solution is x
= 3.
Note:
We divide both sides by 2 rather than 4 in
order to avoid introducing fractions into
the equation.
One way to simplify
is:
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