Answer
Width = 6.0703
Length = 11.0703
Work Step by Step
2∗7∗3=252
252 * 0.8 = new volume = 201.6
The width and length must decrease by the same amount; we can call this length x. We can then now create this equation:
3(12−x)(7−x)=201.6
We can now solve this equation to get the value for x
When we expand it out we get:
5x2−95x+84=0
We can use the quadratic formula, which is:
$\frac{-b+-\sqrt xb^2-4ac}{2a}$
Where a= 5
b=-95
c=84
We then get a value for x as 18.07 and 0.9297
18.... is greater then 12 therefore we can reject this value for x.
We can now subtract 0.9297 from 12 and 7 to give us the width and length.