determinan x + 2y = 7. 4x-y= 10. terima kasih

jawab

x + 2y = 7
4x - y = 10

D= [1...2||4...-1|
D = 1(-1) - 4(2)
D= -1 - 8
D= - 9


DX= [7...2||10...-1]
DX = 7(-1) - 10(2)
DX = -7 - 20
DX = - 27

DY =  [1...7||4...10]
DY = 1(10) - 4(7)
DY = 10- 28
DY = -18

x = DX/X = -27/-9 = 3
y = DY/D = -18/-9  = 2

(x,y) = (3, 2)