Solve the following using the substitution method and find the value of x and y:
-3y = 12
5x + 5y = -45

The correct answer is: -5, -4

In this method, the elimination of the variable can be performed by substituting the value of another variable in an equation. Hence, this method is called the elimination by substitution method.
 -3y = 12 and 5x + 5y = -45
Given:
-3y = 12  …  (1)
5x + 5y = -45 …(2)
The equation (1) can be written as
y = -4
Hence, the value of y is -4.
Now, substituting y= -4 in the equation (2), we get
5x + 5(-4) = -45
5x -20 = -45
5x = -25
x = -5
Therefore, the value of x is -5.
Hence, the solution for the system of linear equations is:
x = -5 and y= -4
To check whether the obtained solution is correct or not, substitute the values of x and y in any of the given equations.
Verification:
Use Equation (2) to verify the solution
5x + 5y = -45
Now, substitute x= -5 and y= -4
5(-5) + 5(-4) = -45
-25 - 20= -45
-45 = -45
Here, L.H.S = R.H.S
Thus, the obtained solution is correct.