Pls ! in which line is a mistake first made when solving the following system of equations by substitution? 2x - y =-4 3x + y = -9line 1: 2x -y = -4y= 3x-9line 2: 2x-(3x-9)=-4 line 3: 2x-3x+9=-4line 4: -1x + 9 = -4line 5: -1x = -13line 6: x = 13

The very first line has an error.

Step-by-step explanation:

When you are solving the second system of equations for y, you need to subtract 3x from both sides and therefore it should be negative.

3x + y = -9

y = -3x - 9

Since the 3x isn't negative in the first line, there is an error.

damm bro the struggle

step-by-step explanation: