Find and correct the error of the following factor. factor by grouping: 3x² + xy2 – 3xy-y? line 1: = (3x² + xy2)+(-3xy – y? ) line 2: = x(3x + y2) - y(3x – y2) line 3: = (x-y) (3x +y? )

3x² + xy2 – 3xy-y? >> 3x² - xy - y

line 1: = (3x² + xy2)+(-3xy – y?)

ANS 3x² - xy - y 《Correct》

line 2: = x(3x + y2) - y(3x – y2)

ANS 3x² - xy +2y²

line 3: = (x-y) (3x +y?)

ANS 3x² - 2xy - y²

If it incorrect, I'm sorry.

maximum area = xy = (16)(32) = 512 ft2

to maximize the area of the garden, the side of the fence parallel to the side of the house should be 32 ft long, and the other two sides should both have length 16 ft.'

source

answer:   x = 3 + √11     and     x = 3 - √11

step-by-step explanation:

x² - 6x + 9 = 11

(x - 3)² = 11

x - 3 = ±√11

    x = 3 ± √11

x = 3 + √11     and     x = 3 - √11