Resoude ses equations
3x( x-7) + 7 = 7
3x(x-7)+7-7=0
2x(x-7)=0
3x=0
x-7=0
x=7 S[ 0, 7}
( x - 5 )² - ( x - 5 ) ( x + 3 ) =0
(x-5)[(x-5)-(x+3)]
(x-5)(x-5-x-3)
(x-5)(-8)⇔8(x-5)
x-5=0
x=5
( x + 2 )² - 4(x-5)² = 0
[(x+2)-2(x-5)][(x+2)+2(x-5)]
(x+2-2x+10)(x+2+2x-10)
(-x+12)(3x-8)
-x+12=0 ou 3x-8=0
-x=-12 3x=8
x=12 x=8/3