Carcass wrote:
\(x < 0\) and \(y > 0\)
Quantity A |
Quantity B |
\(\sqrt{x^2y^2}\) |
\(xy\) |
A) Quantity A is greater.
B) Quantity B is greater.
C) The two quantities are equal.
D) The relationship cannot be determined from the information given.
KEY CONCEPT: The √ notation tell us to take the POSITIVE square root of a value.
For example √25 = 5 and √49 = 7
Also recognize that √0 = 0
In general, we can say:
If k ≥ 0, then √k ≥ 0We have:
QUANTITY A: √(x²y²)
QUANTITY B: xy
QUANTITY AWe know that x² ≥ 0 for ALL values of x
And y² ≥ 0 for ALL values of y
So, x²y² ≥ 0
When we apply the above
rule, we can conclude that √(x²y²) ≥ 0
In other words,
√(x²y²) = some number that's greater than or equal to zero.
QUANTITY BWe're told that x is NEGATIVE, and that y is POSITIVE
So, xy = (NEGATIVE)(POSITIVE) =
some NEGATIVE number.
We get:
QUANTITY A:
some number that's greater than or equal to zero.
QUANTITY B:
some NEGATIVE number.
Answer: A
Cheers,
Brent