Question

2x - 5y = 5
x + y =2
Solve the system of equations

Answer 1

`x = (15)/(7) , \ y = - (1)/(7)`

Explanation:

2x - 5y = 5 ---------- ( 1 )

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

x = 2 - y ---------( 3 )

Substitute x in ( 1 ) :

2( 2 - y) - 5y = 5

4 - 2y - 5y = 5

- 7y = 5 - 4

-7 y = 1

`y =- (1)/(7)`

Substitute y in ( 2 ) :

`x + y = 2\\\\x -(1)/(7) = 2\\\\x = 2 + (1)/(7)\\\\x = (14 + 1)/(7)\\\\x = (15)/(7)`

Answer 2

`{ \bf{2x - 5y = 5 - - - (a)}} \\ { \bf{x + y = 2 - - - (b)}} \\ (a) - 2(b) : \\ - 7y = 1 \\ y = - (1)/(7) \\ x - (1)/(7) = 2 \\ x = (15)/(7)`