Question

What is the solution of this system of linear equations? 3y = x + 6 y – x = 3

Answer 1

3y = x + 6
y = x + 3   Subtract:-

2y = 0 + 3
y =  3/2 = 1.5

Plug this value of y into the first equation:-

3(1.5) = x + 6
x = 4.5 - 6 = -1.5

Answer is x = -1.5, y = 1.5

Answer 2

3y = x + 6
y – x = 3 ----------->  x=y - 3 (substitute in 1st equation)

3y = y - 3 +6
3y - y = 3
2y = 3
y = 2/3

x= y - 3 = 2/3 -3 = 2/3 - 9/3 =  - 7/3

x= - 7/3, y = 2/3