Réponse :
Explications étape par étape
a 4x-5= -3x-4 <=>7x -5 = -4 <=> 7x = 1 <=> x = 1/7
b 4(x+2) =12 <=> 4x +8 =12 <=> 4x = 12-8 <=> x = 4/4 <=> x = 1
c x+1=5x+21 <=> 1 = 4x +21 <=> -20= 4x <=> -5 = x
d √3x+5=x+7 <=> √3x -x +5 =7 <=> √3x - x = 2 <=> x(√3 -1) = 2
<=> x(√3-1)/(v3-1) = 2/(√3 - 1)
<=> x = 2/ (√3-1)
e 3(2x-3) =10x+11 <=> 6x -9 = = 10x +11 <=> -9 = 4x +11 <=> -20= 4x <=> -5 = x
f x² +8 x-4 =x² +x-3 <=> 8x -4 = x -3
<=> 7x -4 = -3
<=> 7x = 1 <=> x = 1/7
c et e ont la même solution.
a et f ont la même solution.
