Résoudre ces équations :
a. 9x – (2 – 7x) = 4 + 3(4x – 1)
9x-2+7x= 4+12x-3
16x-12x= 1+2
4x= 3
x= 3/4 .
b. 4 – 2(3x + 16) = 9x – 4(7 – 2x)
4-6x-32= 9x-28++8x
-6x-28= 17x-28
-6x-17x= - 28+28
- 23x= 0
x= 0 .
c. (x − 1)(x + 3) = (x + 5)(x − 4)
x²-x+3x-3= x²+5x-4x-20
x²+2x-3= x²+x-20
x²-x²+2x-x= - 20+3
x= - 17 .
