Jika 2x^2-(3a-1)x-1(b-4)=0 akar-akarnya x1 and x2. Jika x1+x2=2 dan x1*x2=-5, hasil dari 3a-2b= adalah

Kelas 10 Matematika
Bab Persamaan Kuadrat

2x² - (3a - 1) x - 1 (b - 4) = 0
p = 2; q = -3a + 1; r = -b + 4.

x1 + x2 = 2
-q/p = 2
- (-3a + 1)/2 = 2
3a - 1 = 2 . 2
3a = 4 + 1
a = 5/3

x1 . x2 = -5
r/p = -5
(-b + 4)/2 = -5
-b + 4 = 2 . (-5)
-b = -10 - 4
b = 14

3a - 2b
= 3 . 5/3 - 2 . 14
= 5 - 28
= -23