Can someone please check if these are correct?

Question

quickstudent · Answer

Here is the first one:

quickstudent · Answer

What I want to know is, did I do part b correctly?

anonymous · Answer

$$A = x^2+12x$$
$$A = w \times l$$

You can let width = x 
length = l

$$Area = l*x \implies x^2+12x=l*x$$
Solve for l.

Once you get l you can easily solve for width,

So yes, B is correct.

anonymous · Answer

Make sure you put the dimensions, so 220 ft^2

quickstudent · Answer

Did I completely answer the question there? I know my math is correct, but I am just not sure if I am doing what is being asked for.

anonymous · Answer

Yeah your way is fine as well, 

$$A = x^2+12x \implies 100+120 $$

quickstudent · Answer

Thanks:) Can you check a couple more?

anonymous · Answer

Btw when you factor x^2+12x = x(x+12)

quickstudent · Answer

Yeah, I know, I just wrote it that way because I had to use the guess and check method, which I learned had to result in an answer that looks like that. Both answers are correct, right?

anonymous · Answer

Yes :)

quickstudent · Answer

Ok:) Here's the next one.

anonymous · Answer

It's the same process as the last :P

quickstudent · Answer

I actually kind of already know the rest are correct, I just have this habit of making sure about everything.

anonymous · Answer

b is not right. You plugged in the given value to the area expression, not the length and width.

quickstudent · Answer

But I don't see any other expression than that one. @albertedison98

radar · Answer

@quickstudent Another way to look at this is, provided you are familiar with "long division" is to look at it like this:  A = l * w so|dw:1407077119617:dw|