Substitute this simultaneous linear equation 2x + 2y = 14 \\ 5x - 2y = 14 ​

Question

Substitute this simultaneous linear equation

`2x + 2y = 14 \\ 5x - 2y = 14`
​

Answer 1

`2x + 2y = 14 \: .....(1) \\ \\ 5x - 2y = 14 \: .....(2)`

From equation (1) ;

`2x + 2y = 14 \\ \\ 2y = 14 - 2x \\ \\ y = (14 - 2x)/(2) \\ \\ y = 7 - x`

Substitute in equation (2)

`5x - 2y = 14 \\ \\ 5x - 2(7 - x) = 14 \\ \\ 5x - 14 + 2x = 14 \\ \\ 7x = 14 + 14 \\ 7x = 28 \\ \\ x = (28)/(7) \\ \\ x = 4`

`y = 7 - x \\ y = 7 - 4 \\ \\ y = 3`