Answer:
I really want to help you but I am really confused with those topics. I am very sorry.
Step-by-step explanation:
Answer:
y = -2x - 1
Step-by-step explanation:
Parallel lines have the same slope, so the slope will also be -2.
Plug this slope and the given point into the equation y = mx + b and solve for b:
y = mx + b
5 = -2(-3) + b
5 = 6 + b
-1 = b
Then, plug this and the slope into the equation:
y = -2x -1 will be the equation
Step-by-step explanation:
Permutation
:The number of ways to choose a sample of r elements from a set of n distinct objects where order does matter and replacements are not allowed.

Factorial
: There are n! ways of arranging n distinct objects into an ordered sequence.
Considering a situation when n = r in a permutation, nPr reduces to n!, a simple factorial of n.
Proof: 3P3 = 3!
n = 3 and r = 3

But 0! = 1
3P3 = 3!
Answer:
(a×b)×c = 0 means that vector c parallel to vector (a×b). But because (a × b) ⊥ a and (a -b) ⊥ b so
c ⊥ a and c ⊥ b.
Hope this helps, have a nice day! :D