diketahui 5x - 2y = -1 dan x - 2y = 3.nilai dari 2x + 5y adalah

kyaknya itu bener....

5x - 2y = - 1 ... ( 1 )
x - 2y = 3 ... ( 2 )

( 1 ) - ( 2 )
4x = - 4
x = - 4/4
x = - 1

x - 2y = 3
( - 1 ) - 2y = 3
- 2y = 3 + 1
- 2y = 4
y = 4/-2
y = - 2

x = - 1
y = - 2
2x + 5y = 2( - 1 ) + 5( - 2 ) = - 2 - 10 = - 12