SOLVING SIMULTANEOUS LINEAR EQUATIONS 1

Example 1

The total age of Ali and Halim is 35 years.  Halim is 5 years older than Ali.  Find their ages.

Solution:

Let x = Ali's age

           y = Halim's age

      x + y = 35   ------------------------(1)

         y = x + 5   -----------------------(2)

Subtitute (2) into (1)

x + x + 5 = 35

    2x + 5 = 35

                2x = 35 - 5

           2x = 30

               x = 30/2

            x = 15

Subtitute x = 15 into (2)

      y = 15 + 5

y = 20

Therefor, Ali is 15 years old and Halim is 20 years old.