Question

Please me with this

thanks

What is the solution of the system of equations?
3x + 2y + z =7
5x + 5y + 4z =3
3x + 2y + 3z =1

Answer 1

minus the first from the 3rd equation
we get
3x-3x + 2y-2y + 3z -z = 7-1
2z = 6
z = 3
plug into the 2nd equation to get
5x+5y = 3-12 = -9
plug into the first equation to get
3x+2y = 4
Multiply the 2nd equation by 2 and the 1st by 5
10x+10y = -18
15x+10y = 20
minus first from the 2nd
5x = 20 - -18
= 5x = 38
x = 38/5
y = (20 - 38 * 3)/10

Check My work I might have made a mistake

Answer 2

I get (x,y,z) = (4, -1, -3)

Your very first line is wrong.
Should be 1-7, not 7-1
z = -3

The rest surely follows.

Answer 3

srry :(

Answer 4

thanks