Réponses

2014-10-26T19:27:25+01:00
A/
3x +8 = 2x-5
3x -2x = -5 -8
x = - 13

b/(2x+3)(-5x+1)
-10x² +2x-15x +3
-10x² -13x +3

c /-2(3x+25) = x+10
-6x -50 -x = 10
-7x = 10+50
-7x = 60
x = -60/7

d / 4 -(x-5)² = (x+4)² -37
4 -(x²-20x+25) = x²+8x+16-37
4-x²+20x-25 -x² -8x =  -21
12x  -21 = -21
12x = -21+21
12x = 0
x = 0/12
x = 0


je te laisse faire le reste