How do you solve the system of equations algebraically #x-y-z=7, x+2y+3z=-12, 3x-2y+7z=30#?
Multiply the first equation by -3 first. Then go ahead, x=2/26; y=-226/26 and z=46/26
When you multiply the first equation by -3, you will get:
Then combine this equation with the second. Yielding,
When you see y (in the first (original equation)), write this and for the second original equation do the same.
You will get
Finally, you can easily solve using any original equation.