We have

so this is indeed a difference of squares. Factorizing would give

making the answer D.
We can further factor the first term here and write

but that's clearly out of the scope of this question.
Answer: w=12, y=6√3
Step-by-step explanation:
Looking at the figure, we can split the triangle into 2 separate triangles. One on the left and one on the left. The triangle on the right is a 30-60-90 triangle. For this triangle, the hypotenuse is 2x in length. This is directly opposite of the right angle. The leg opposite to 30° is x in length. The leg opposite 60° is x√3 in length. Once you know the length of one side, you can plug in x to find the length of the other legs.
In this case, w and y are located on the same 30-60-90 triangle. Normally we would focus on that triangle to find our values, but in this instance, we don't have any values. We have to use the left triangle to find the leg that both triangles share.
The left triangle is a 45-45-90 triangle. For this triangle, the legs opposite of 45° is x in length. The hypotenuse is x√2. Since we know the hypotenuse, we can use it to find x.
x√2=8
x=8/√2
x=5.7 or 6 [Let's use 6 so that it is easier to work with a whole number]
Now that we know x, we can find w and y. Going back to the right triangle, we know the hypotenuse is 2x. We plug in 6 to find the length.
w=2x
w=2(6)
w=12
We know the leg opposite of 60° is x√3. We can plug in x.
y=6√3
Formula for the area of the triangle:
1/2 bh
b = base
h = height
#6.
Area = 36 in²
Base = 18 in
36 = 1/2(18)h
36 = 9h
36 ÷ 9 = h
4 = h
height = 4 in
#7.
Area = 2 ft²
Height = 1 ft
2 = 1/2 b (1)
2 = 1/2 b
2 ÷ 1/2 = b
4 = b
Base = 4 ft
#8.
Area = 42 in²
Base = 12 in
42 = 1/2 (12) h
42 = 6h
42 ÷ 6 = h
7 = h
Height = 7 in
Notice that the answers have no exponents (²). That is because they are used only on the area of shapes as units.
Since you find the area by multiplying things together, for example x · x = x², the exponent is there.
You do not need to worry about this being in the calculation. This will just be in units such as:
cm²
ft²
in²
m²
Just remember to use these exponents in the units for the areas.