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y= 4x - 9
y= x - 3

can someone pls help me solve this system of equations (using substitution)


Sagot :

Answer:

  (x, y) = (2, -1)

Step-by-step explanation:

You want to solve this system using substitution.

  • y = 4x -9
  • y = x -3

Substitution

It works best to substitute for a variable that you already have an expression for. Here, you have two expressions for y. Substituting both for y, you get ...

  y = y

  4x -9 = x -3

  3x = 6 . . . . . . . . add 9-x to both sides

  x = 2 . . . . . . . . divide by 3

  y = 2 -3 = -1 . . . . substitute for x in the second equation

The solution is (x, y) = (2, -1).