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Ticket: 5c231523f363b Rayzle
26 Dec 12:44

x2- bx + b + 2 = 0 

Jika 2x1 + x2 = 8 maka b adalah...

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m43p05
27 Dec 18:59

x2- bx + b + 2 = 0 

x1 + x2 = b  dan 2x1 + x2 = 8

hasil eliminasi:

x1 = 8 - b substitusi ke persamaan kuadrat:

(8 - b)2 - b(8 - b) + b + 2 = 0

64 - 16b + b2 - 8b + b2 + b + 2 = 0

2b2 - 23b + 66 = 0 

(2b - 11)(b - 6) = 0 

b = 11/2 atau b = 6

Rayzle
27 Dec 20:20

Makasih!