tolong bantu nomor 8 sampai 11, thankss :)

jawab

8
x² +4x - 3 = 0
x² + 4x = 3
(x + 2)² = 3 + 4
(x + 2)² = 7 →(x +a)² = b
a = 2 ,  b = 7

9
2x² +8x - 5 =0
x² + 4x - 5/2 = 0
(x² + 4x) = 5/2
(x + 2)² = 5/2 + 16
(x + 2)² = 37/2 → (x + a)² = b
a -2 , b =  37/2

10
x(x-2) = 5
x²  - 2x = 5
(x - 1)² = 5 + 1
(x - 1)² = 6  → (x + a)² = b
a = -1 , b =  6

11
4 - 5x - x² =0
x² + 5x - 4= 0
(x² + 5x) =  4
(x + 5/2)² = 4 + 25/4
(x + 5/2)² = 41/4  → (x + a)²  = b
a= 5/2
b = 41/4