Please..bantu nomor 7-9 . besok kumpul!! jangan asal

7) x² + ax – 4 = 0

p + q = -a/1 = -a

p.q = -4/1 = -4

p² + q² = ( p + q)² – 2pq

p² + q² = (-a)² – 2(-4)

p² + q² = a² + 8

p² -2pq + q² = 8a

p² + q² – 2pq = 8a

(a² + 8) – 2(-4) = 8a

a² – 8a + 16 = 0

(a – 4)² = 0

a = 4

jawaban : c

8) 6x² + x – 5 = 0

6x² + 6x – 5x – 5 = 0

6x(x + 1) – 5(x + 1) = 0

(6x – 5)(x + 1) = 0

faktor-faktornya adalah :
(6x – 5) dan ( x + 1)

jawaban : a

9) bingung