Given the equation √2x - 5 = 2, solve for x and identify if it is an extraneous solution.
Solution:
The given equation is: x√2 - 5 = 2
x√2 = 2 + 5
x√2 = 7
Squaring both sides we have
2x2 = 49
x2 = 49/2
x = ±7/√2
To test whether there is an extraneous solution or not we will substitute the two values in the original equation and verify.
1. x = +7/√2
Substituting x = +7/√2 in (x√2 - 5 = 2) we get,
(7/√2)√2 - 5 = 2
7 - 5 = 2
2 = 2. Hence x = +7/√2 is a legitimate solution and not extraneous.
2. x = -7/√2
Substituting x = - 7/√2 in (x√2 - 5 = 2) we get,
(-7/√2)√2 - 5 = 2
-7 -5 = 2
-12 = 2. This is inconsistent as we know that -12 is not equal to 2.
Therefore x = -7/√2 is an extraneous solution.
Given the equation √2x - 5 = 2, solve for x and identify if it is an extraneous solution.
Summary:
The equation √2x - 5 = 2 when solved for x has an extraneous solution x = -7/√2.
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