apabila x,y,z membentuk barisan arimatika dgn x+y+zadlh 15 dan xy=15 tentukan nilai 2x-y+z=...........

misal, x = a
y = a + b
z = a + 2b

x + y + z = a + a + b + a + 2b = 3a + 3b = 15
3a + 3b = 15
3(a + b) = 15
a + b = 5

xy = a(a + b) = a(5) = 5a = 15
5a = 15
a = 3

a + b = 5
3 + b = 5
b = 2

2x - y + z = 2a - (a + b) + (a + 2b)
= 2(3) - (3 + 2) + (3 + 2(2))
= 6 - 5 + 7
= 8