C'est pour un devoir de 4ème aidez moi

a)
- 4 * 2 = - 8 + 3 = - 5 
5 * 2 = 10 + 3 = 13
x * 2 = 2x + 3 = 2x + 3

b)
2 x (- 1) + 3
= - 2 + 3
= 1

c)
2x + 3 = 8
2x = 8 - 3
2x = 5
x = 5/2
x = 2,5

-4 x 2⇒ = -8 +3⇒ -5

5 x 2⇒= 10 + 3 ⇒13

X x 2⇒ 2X +3 ⇒ 2X+3
b) calculons 2X + 3 losque X = -1
2x(-1) +3 = -2 + 3 
               = 1
2X+3 = 8
2X = 8-3
2X = 5
 X = 5/2