Exercice 86
[tex]a. \\ x(x+4)=-4 \\ x(x+4)+4=0 \\ x^{2} +4x+4=0 \\ (x+2)^{2}=0 \\ x+2=0 \\ x=-2 \\[/tex]
[tex]b. \\ (x+1)^{2}*[(x+1)-1]=0 \\ (x+1)^{2}*x=0 \\ x=-1 \\ ou \\ x=0[/tex]
[tex]c. \\ 2x(2x-1)=6(2x-1) \\ 0=6(2x-1)-2x(2x-1) \\ 0=(2x-1)(6-2x) \\ x=0,5 \\ ou \\ x=3[/tex]
[tex]d. \\ (x+2)^{2}-3(x+2)=0 \\ (x+2)*[(x+2)-3]=0 \\ (x+2)(x-1)=0 \\ x=-2 \\ ou \\ x=1[/tex]
Exercice 70
[tex]a. \\ 2( \frac{x}{3} -1)-(x- \frac{1}{3} )=0 \\ \frac{2x}{3} -2-x+ \frac{1}{3} =0 \\ \frac{2x+1}{3} - \frac{6}{3} - \frac{3x}{3}=0 \\ \frac{-x-5}{3} =0 \\ -x-5=0 \\ x=-5[/tex]
[tex]b. \\ x-5=-21 \\ x+16=0 \\ x=-16[/tex]
[tex]c. \\ \frac{1}{4} x+ \frac{6}{4} x- \frac{3}{8} =0 \\ \frac{7}{4} x- \frac{3}{8} =0 \\ \frac{14x-3}{8} =0 \\ x= \frac{3}{14} [/tex]
[tex]d. \\ x-3=4x+2 \\ -5=3x \\ x= \frac{-5}{3} [/tex]
