Bonjour,
1) x = -3
donc : -2(x+2) = -2(-3+2) = 2
3x+4 = 3(-2)+4 = -2
(x+7)² = (-3+7)² = 16
x²-2x+4 = (-3)²-2(-3)+4 = 9+6+4 = 19
2) 3x²-11x-2 n'est pas réductible
7y+10-13y = 10-6y
8-5d+3 = 11-5d
8-x²+4x+7x² = 6x²+4x+8
3) 5(6-a) = 30-5a
-6(2b-5) = -12b+30
7c(2-9c) = 14c-63c²
11+2(d-5) = 11+2d-10 = 2d+1
4) 27-21x = 3(9-7x)
5y²+2y = y(5y+2)
7z²+z = z(7z+1)
9w-12w² = 3w(3-4w)