Solve the following pair of linear equations: 21x + 47y = 110 and 47x + 21y = 162

21x + 47y = 110 ……(1)

47x + 21y = 162 ……(2)

Add EQ 1 and EQ 2

21x + 47y + 47x + 21y = 110 + 162

68x + 68y = 272

68 (x + y) = 68 ……(4)

x + y = 4 EQ 3

Subtract EQ 1 from EQ 2

21x + 47y – 47x – 21y = 110 – 162

26x – 26y = 52

26 (x – y) = 26 ……(2)

x – y = 2 EQ 4

Add EQ 3 and EQ 4

2x = 6

x = 3

Put x in EQ 3

3 + y = 4

y = 2