2x²-6x-p=0 adalah x1 dan x2 jika x1-x2=5 nilai p adalah

jawab
Persamaan kuadrat
2x²-6x - p = 0
a= 2
b = - 6
c = -p

x1. + x2 = - b/a =  -(-6)/2= 3
x1. x2 = c/a = - p/2
x1- x2 = 5

x1 + x2 = 3
x1 - x2 = 5 .....(+)
2x1 = 8
x1 = 4

x1 + x2 = 3
x2 = 3 - x1
x2 = 3-4
x2 = - 1

x1 .x2 =  - p/2
4(-1) = -p/2
-4 = -p/2
-p = 2(-4)
p = 8