Question

I don't understand the first step to eliminating these equations
x-y+5z=4 5x+z=0 x+4y+z=-16

Answer 1

z=-5x

x-y-25x=4
x+4y-5x=-16

[-24x-y=4] *4
-4x+4y=-16
------------- +
-100x=0 => x=0 =>z=0 => y=4

Answer 2

how do you know to do z=-5x

Answer 3

and how do you solve -5x=z

Answer 4

5x+z=0
put 5x to the left and you get z=-5x
later substitute this value of z in the other equations

Answer 5

okay and then how does z = 25x

Answer 6

x-y+5z=4
x-y+5(-5x)=4
x-y-25x=4

Answer 7

okay

Answer 8

so in x-y-25x=4
x+4y+z=-16 what are you solving for