Answer:
A. the difference of two squares
Step-by-step explanation:
Please use the symbol " ^ " to indicate exponentiation.
Then we have x^2 - 11^2, which is the difference of two squares:
x^2 is a square, the square of x; and 11^2 is a square, the square of 11.
A. the difference of two squares
Note that a "difference of squares" is easily factored:
a² - b² = (a - b)(a + b)
and so your x² - 11² factors as follows: (x - 11)(x + 11)
First, we must find the common denominator (12) ✵
10/12-6/12 ✵ ✵ ✵ ✵
Now, why 10? ✵ ✵ ✵
Because we CAN'T just take the denominator and change it; we must change both the denominator AND the numerator:
✵ • - ○
4/12 ✧ ✩ ✶ ✺ ✱
We can simplify, or reduce, this fraction: ✱ ✱
1/3 ✩ ✦ ✤
I hope it helps!

I think the answer is 0.31!
Since they are similar, you need to find the ratio of similarity (I made up the term, there is probably a correct one that I can’t remember).
If you divide 16/40, you’ll find that that ratio is 2.5. So then you just multiply 16 x 2.5. You’ll get 18.
18 is the length of the top of the trapezoid.
You set 18=2x+4 and solve it algebraically. Subtract 4 from both sides.
14=2x
Divide by 2 and x=7
(You can also check that the ratio is right by 16/18 is the same decimal value as 40/45. You’ll get .88888...)