Answer:
The two numbers are
518
694
Step-by-step explanation:
As per requirements the two equations will be
X+Y=1212
X-Y=518
When we subtract these equations we get
X=1212-518
X=694
Now put the X value and find the Y value in any equation
X+Y= 1212
Y=1212-X
Where X = 694
Y=1212-694
Y=518
X=694 and Y=518
Answer:
D supplementary angles
Step-by-step explanation:
It is 12 sense the perimeter is the outside of the square you have to add the 2 numbers by themselves because they are the same measurement and 5+5=10 1+1=2 10+2=12
The new equation after the expression equivalent to x from the first equation is substituted into the second equation is: 
Step-by-step explanation:
We will solve the initial steps for substitution method for finding the correct answer
Given equations are:

From equation one

Putting x = -4y-9 in equation 2

Hence,
The new equation after the expression equivalent to x from the first equation is substituted into the second equation is: 
Keywords: Linear equations, variables
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