Question

Find the values of x, y and z from the following equation

`[(x + y + z),(x + z),(y + z)] = [(9),(5),(7)]`

Answer 1

x + y + z = 9   ...(1)

x + z = 5 ...(2)

y + z = 7   ...(3)

(1) ⇒ x + y + z = 9
(2) ⇒ x + 0 + z = 5
           (–)    (–)    (–)  
(1) – (2) ⇒  y   =   4

Substitute the value of y = 4 in (3)

y + z = 7

4 + z = 7

z = 7 – 4

= 3

Substitute the value of z = 3 in (2)

x + 3 = 5

x = 5 – 3

= 2

∴ The value of x = 2, y = 4 and z = 3