I think the answer should be 6.
Answer:
Option 2nd is correct that is 
Step-by-step explanation:
We have given the vertices of a parabola
General equation of parabola is:

Here, (h,k) is vertex of the parabola
Here, h=1 and k=2 and a=1
On substituting the values in the general equation of the parabola we get:


Therefore, option 2nd is correct.
Answer:
L = 6, w = 2
Step-by-step explanation:
Let w = width of rectangle
Let L = length of rectangle
w = L - 4
Area of rectangle = Lw
L (L - 4) = 12
L^2 - 4L = 12
L^2 - 4L - 12 = 0
(L - 6)(L + 2) = 0
L - 6 = 0
L = 6 (the other option doesn't work because dimensions can't be negative)
w = L - 4
w = 6 - 4
w = 2
Double check
A = Lw
A = 6 x 2
A = 12
It matches so we are right.
Let
be the inital number of Timmy's marbles, and
be the inital number of Ben's marbles.
At the beginning, "Timmy had 3/4 of what Ben had", which means

(I wrote the equation in an equivalent form to avoid denominators)
Then, Ben gives 36 marbles to Timmy. So, now Ben has
marbles, and Timmy has
marbles. The new ratio is 1 to 3 in Timmy's favour, so we have

(same as before)
So, we have the following linear system:

From the first equation we know that
, so the second equation becomes

Now that we know the value for
, we can simply plug it into the first equation to get

The angles of a rectangle are equal ALWAYS.
The rectangle has 4 angles, each angle is a right angle or has a measurement of 90°. Total of all interior angle is 360°.
Just like a rectangle, a square has an angle that is always equal because its angles are all right angles.