Persamaan kuadrat maka nilai c adalah?

Persamaan kuadrat maka nilai c adalah?

${x}^{2} + bx - 16 = 0$
salah satu akar = 2
substitusi
${2}^{2} + b(2) - 16 = 0$
2b + 4 – 16 = 0
2b – 12 = 0
2b = 12
$b = frac{12}{2} = 6$
$3 {x}^{2} + bx + c = 0$
$3 {x}^{2} + 6x + c = 0$
akar kembar maka
D = 0
${b}^{2} - 4ac = 0$
${6}^{2} - 4(3)c = 0$
36 – 12c = 0
12c = 36
$c = frac{36}{12} = 3$