Question

-3x + 7y = -16
-9x + 5y = 16

Part A: Create an equivalent system of equations by replacing one equation with the sum of that equation and a multiple of the other. Show the steps to do this.

Part B: Show that the equivalent system has the same solution as the original system of equations.

Answer 1

-3(-3x-7y=-16)
have :
9x-21y=48
Sum :
-9x + 5y = 16
and 9x-21y=48
-9x+9x+5y-21y=64
have :
-16y=64
y=-64/16
y=-4
x :
-3x + 7y = -16
-3x-28=-16
-3x=28-16
-3x=12
x=-4
Got it ?;)

Answer 2

Got it! Thank you for showing your work!! This really really helped! Thank you :)