We are given that,

We need to find the value of (x + y + z).

We know by the property of matrices,

This implies,

a₁₁ = b₁₁, a₁₂ = b₁₂, a₂₁ = b₂₁ and a₂₂ = b₂₂

We have,

Therefore,

xy = 8 …(i)

4 = w …(ii)

z + 6 = 0 …(iii)

x + y = 6 …(iv)

We have the equations (i), (ii), (iii) and (iv).

We just need to find the values of x, y and z. So,

From equation (iii),

z + 6 = 0

⇒ z = -6

Now, let us find (x + y + z).

Substituting z = -6 and the value of (x + y) from equation (iv),

x + y + z = (x + y) + z

⇒ x + y + z = 6 + (-6)

⇒ x + y + z = 6 – 6

⇒ x + y + z = 0

Thus, the value of (x + y + z) is 0.