1-dévellopper puis réduire 2(y+3)+5(2y-5) 6(5y+3)-8(-3+6y) 2-resoudre les équations 2x-3=-7 4x=2x+3 5x-2(3x+1)=2(x-7) t sur -7 =5 sur 2 4y sur 5 =2 sur 15



Sagot :

2(y+3)+5(2y-5) = 2y+6 + 10y -25 = 12y -19

6(5y+3) -8 (-3+6y) = 30y +18 - (-24+48y) = 30y +18 +24 -48y = -18y +42

 

2x -3 = -7

2x = -7+3

2x = -4

x = -2

 

4x = 2x+3

4x-2x = 3

2x = 3

x = 3/2

 

t/-7 = 5/2 = 2t/-14 = 35/14

2t = 35

t = 17.5

4y/5 = 2/15 = 12y/15 = 2/15

12y = 2

y = 2/12 ou 1/6