Question
Find the values of.x, y and z from the following equations :

Solution
We are given that
By definition of equality of matrices.
x.+ y + z = 9 ,..(1)
.x + z = 5 ...(2)
y + z = 7 ...(3)
Subtracting (2) from (1), y = 4
Subtracting (3) from (1). x = 2
∴from (2), 2 + z = 5 ;⇒ z =3
∴x = 2, .y = 4, z = 3