Question

Which ordered pair is the solution to the system of equations?

Answer 1

To find the solution, we use the substitution method. 

x+y=-1
x-3y=11

x+y = -1-y
  -y       

x = -1-y

Now apply the value of x into the other equation.

x-3y=11
-1-y-3y = 11

Combine like terms

-4y -1 = 11
       +1    +1
-4y = 12

-4y = 12
-4y/-4 = 12/-4
y = -3

Now, apply the value of Y to one equation to find x.

y = -3

x -3 = -1
   +3   +3  
 
x= 2

Now we have the value for both, x and y.
x = 2
y =-3

Final answer: A. (2, −3)