Question

The area of a rectangular pool is given by the trinomial 8y2 + 4y – 12. What are the possible dimensions of the pool? Use factoring.

Answer 1

8y2+4y-12 = 4(2y2+y-3) = 4(2y2+3y-2y-3)=4(y(2y+3)-(2y+3))=4(y-1)(2y+3)=0 say
so either y-1=0 or 2y+3=0
or y=1 or y=-3/2
as dimension cannot be negative.so valid y for rectangle is 1

Answer 2

8y2 + 4y – 12 =2(4y2 + 2y -6)
= 2(2y-2)(2y+3)

L=4y+6 W=2y-2
OR
L= 2y+3 W=4y-4

Answer 3

(–2y – 2) and (–4y – 6)
(2y – 2) and (4y + 6)
(2y – 2) and (4y + 6)
(2y + 2) and (4y – 6)

Answer 4

from the options
(2y – 2) and (4y + 6)
fits