Answer:
Step 1: Equation at the end of step 1
(((x^{2} )-4xy)+(4(((x
2
)−4xy)+(4 ×(y^{2} )))-3^{2} -z^{2}(y
2
)))−3
2
−z
2
Step 2: Equation at the end of step 2
(((x^{2} )-4xy)+2^{2} y^{2} )-3^{2} z^{2}(((x
2
)−4xy)+2
2
y
2
)−3
2
z
2
Step 3: Final Result
x^{2} -4xy+4y^{2} -9z^{2}x
2
−4xy+4y
2
−9z
2
