saya minta tolong di jawab ya cara no 4 soalnya saya tidak tau caranya (mohon di bantu ya (

f(x) = 2x³ + px² + 7x + 6 = 0
x1 = 2 sub ke f(x)
2(2)³ + p(2)² + 7(2) + 6 = 0
16 + 4p + 14 + 6= 0
4p + 36 = 0
p = -9

f(x) = 2x³ - 9x² + 7x + 6
a = 2, b = - 9, c = 7 , d  =6
x1+x2+x3 = -b/2 = -(-9)/2 = 9/2 = 4,5