Got this problem on a test:
12 + √2x-1 = 4
Okay, so then I subtract 12 from both sides:
√2x-1 = -8
2x - 1 = 64 I then square both sides...
2x = 65 Add 1 to each side
x = 65/2 Divide both sides by two.
However, that answer doesn't work. Are there simply no solutions, then?
That is correct, there are no solutions. Not every equation is a true statement. You always check the validity of your answer by plugging into the original equation.
Please go here:
In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
That answer is the solution to
-12 + √(2x-1) = -4
When you square you cannot help but introduce 'solutions' to this alternative equation as well so you were right to check the value you had.
Children are not defined by school ...........The Fonz
You cannot teach a man anything; you can only help him find it within himself..........Galileo Galilei
Even when you got √2x-1 = -8 you could've said that there are no solutions, because a square root of a positive number is always positive...
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