Carcass wrote:
Quantity A |
Quantity B |
\((2x+3y)^2\) |
\(4x^2+6xy+9y^2\) |
A)The quantity in Column A is greater.
B)The quantity in Column B is greater.
C)The two quantities are equal.
D)The relationship cannot be determined from the information given.
Kudos for the right answer and explanation
Question part of the project GRE Quantitative Reasoning Daily Challenge - (2021) EDITIONGRE - Math BookUse FOIL to expand and simplify Quantity A:
QUANTITY A: \((2x+3y)^2=(2x+3y)(2x+3y)=4x^2+6xy+6xy+9y^2=4x^2+12xy+9y^2\)
QUANTITY B: \(4x^2+6xy+9y^2\)
Subtract \(4x^2\) and \(9y^2\) from both quantities to get:
QUANTITY A: \(12xy\)
QUANTITY B: \(6xy\)
Subtract \(6xy\) from both quantities to get:
QUANTITY A: \(6xy\)
QUANTITY B: \(0\)
If \(x=0\) and \(y=0\), but then
the two quantities are equalIf \(x=1\) and \(y=1\), but then
Quantity A is greaterIf \(x=-1\) and \(y=1\), but then
Quantity B is greaterAnswer: D