Answer:
if you have y= 2x, y is in terms of x and you can input different values of x to obtain corresponding values outputs of y.
The first step for solving this problem is to multiply both sides of the bottom equation by -3.

Add the two equations together.
6x - 9y - 6x + 9y = 16 - 21
Eliminate the opposites.
-9y + 9y = 16 - 21
Remember that the sum of two opposites equals 0,, so the equation becomes the following:
0 = 16 - 21
Calculate the difference on the right side of the equation.
0 = -5
This means that the statement

is false for any value of x and y. That means that the answer to your question is (x,y) ∈ ∅,, or no solution.
Let me know if you have any further questions.
:)
Step-by-step explanation:
dont stress just move onto the next question :)
Simplifying
n + -16 = m
Reorder the terms:
-16 + n = m
Solving
-16 + n = m
Solving for variable 'n'.
Move all terms containing n to the left, all other terms to the right.
Add '16' to each side of the equation.
-16 + 16 + n = 16 + m
Combine like terms: -16 + 16 = 0
0 + n = 16 + m
n = 16 + m
Simplifying
n = 16 + m