Question

The sum of the three numbers is 8, twice the second number when added to the first number gives 7. On adding the twice of the sum of first and second members to thrice the third number, we get 20. Find the numbers using matrix method using elementary row transformations.

Answer 1

Answer:

let the no. be x

2x

2x+7+20=8

2x+7=20-8

2x+7=12

2x=12-7

2x=5

x=2.5