Step-by-step explanation:
the area is
length × width
(3x - 2) × width = 9x² - 4
to find width we could do a real polynomial division or simply recognize the fact that
(a + b)(a - b) = a² - b²
and we see that in our area calculation we are missing the (a + b) factor.
so, width = (3x + 2)
but if you want the division :
9x² - 4 : 3x - 2 = 3x + 2
- 9x² - 6x
-----------------
0 6x - 4
- 6x - 4
----------------------
0 0
again, width = (3x + 2)
2x + 2y=132
xy=1080
Let x=1080/y
2160/y + 2y=132
2y^2 - 132y +2160=0
2(y^2-66y+1080)=0
2(y-30)(y-33)=0
y=30 or y=33
(36,30) or (30,36)
So... x=30,36 and y=36,30. Either way, the answer is 30 by 36 or 36 by 30.
The Answer is A: 13.1 in^2
