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Comment on Square Root with x and y
When you give us these
It takes time.
It takes time.
You might want to go back and rewatch the video on solving equations with roots ; https://www.greenlighttestprep.com/module/gre-algebra-and-equation-solvi...
That will help.
Also, be sure to try the additional practice questions in the Related Resources box beneath that video lesso
I took the square root of 9x
Be care, the square root of
Be care, the square root of (9x² + y²) does NOT equal 3x + y.
IF the square root of (9x² + y²) = 3x + y, then it would also have to be the case that (3x + y)² = 9x² + y²
However, when we apply the FOIL method (https://www.greenlighttestprep.com/module/gre-algebra-and-equation-solvi...), we find that...
(3x + y)² = 9x² + 6xy + y²
In general, √(a + b) ≠ √a + √b [this is what you did]
We can demonstrate this with some numbers.
Notice that √(9 + 16) ≠ √9 + √16
Why can't we subtract the 9x
Thanks.
You can always subtract the
You can always subtract the same amount from both sides of an equation.
Can you tell me what point in the solution you would do this? Perhaps show some steps in your solution.
How can we divide both side
I think you're confusing
I think you're confusing equations with inequalities.
With inequalities, we can't divide both sides by a variable, unless we're certain that the variable is a certain sign.
With equations, we can always divide both sides by a variable, as long as the variable does not equal 0.
If xy was stated to be equal
Yes, that would be wrong.
Yes, that would be wrong.
Cheers,
Brent
I can see a lot of progress.
Yes, I can see how this
Yes, I can see how this question could take some time to answer.
The important thing to remember is that the more practice questions you answer, the faster you'll eventually become.