The answer in the problem will be B I believe
In this problem, we need to plug in the given x values for

and find a and b.
When we plug in 1, we get:

Simplify:



We got our first statement about the values of the variables. If we find one more we can find those 2 variables.
We have another given root: 4.
Plug it in:




Now we have our second one. We can combine them:

I use elimination method which is easier here.
Multiply the top equation by -1:

Add them up:

Simplify:

Now we have a, we can plug in one of those equations to find b:



So, the answers are

and

.
7*4=28
7-4=3
so the width is 4 feet and the length is 7 feet
Density = m/v with mass being in grams and volume in mL......
192 grams/250 mL = 0.768 g/mL
2(wl+hl+hw)=2·(14·2+11·2+11·14)=408