Carcass wrote:
Which of the following is equal to −12x−14y+1xy+18 ?
A. (x−4)(2−y)8xy
B. (x−2)(y−4)8xy
C. (x−4)(y−2)8xy
D. (x+2)(4−y)8xy
E. (x−2)(4−y)8xy
First, find a common denominator:
8xyRewrite each expression using 8xy as the denominator:
−4y8xy−2x8xy+88xy+xy8xyAdd up the numerators:
−4y−2x+8+xy (since the denominator is the same in all answer choices, we can disregard it)
Group the x terms together and the y terms together:
xy−4y−2x+8Factor each group:
y(x−4)−2(x−4) And distribute:
(x−4)(y−2)Only one answer choice matches that numerator.
Answer: C