Algebra-2

Given System of Equations
2x + y = 0  (Equation 1)
x + 3y - z = -11  (Equation 2)
7x + 5y + 4z = 21  (Equation 3)

Step 1: Solve Equation 1
From Equation 1, we can express (y) in terms of (x):
2x + y= 0
y = -2x (Equation 4)

Step 2: Substitute y = -2x into Equation 2
Now, we substitute y into Equation 2 to express (z) in terms of (x):
x + 3(-2x) - z = -11
x - 6x - z = -11
-5x - z = -11
-z = -11 + 5x
z = 11 - 5x (Equation 5)

Step 3: Substitute y = -2x an...