It would be D because when you solve for the vertex, first it says in the parentheses to add 3 which is to move 3 to the left. Then you see outside the parentheses to subtract 2 which is to move down. This is how you know it is D
When you are adding you are ,say you have the number 4 and you need to add it to 5 you are basically mushing those two numbers together and seeing what you get, and I got 9. with multiplying you are multiplying it by itself however many times you need to, to find out the answer. :)
X*26=180 subtract 26 from 180 then you will find x.
That's a 33% increase.
I calculated this using the formula:

Where n = the new value (16 in your question), o = the old value (12 in your question) and the result is outputted as a percent increase. You can check that this is correct by finding 33% of 12, adding the result to 12, and checking that the result equals your "new" number.
Note that 33% is only an approximation as your question requires a number rounded to the nearest whole.
Answer:
x = 2
y = 7
Step-by-step explanation:
5x+2y=24 -------------->equ 1
8x+2y=30 -----------> equ 2
equ 1 - equ 2 =====> -3x = - 6
x = -6 / -3 = 2
x = 2
Put x = 2 in equ 1,
5*2 + 2y = 24
10 + 2y = 24
2y = 24 - 10
2y = 14
y = 14/2
y = 7