Répondre :
Bonsoir,
a)
1<2x-5<3
<=> 1 + 5 < 2x < 3 + 5
<=> 6/2 < x <8/2
<=> 3 < x < 4
b)
-3<2+5x<7
<=> -3 - 2 < 5x < 7 - 2
<=> -5/5 < x < 5/5
<=> -1 < x <1
Bonsoir,
a)
1<2x-5<3
<=> 1 + 5 < 2x < 3 + 5
<=> 6/2 < x <8/2
<=> 3 < x < 4
b)
-3<2+5x<7
<=> -3 - 2 < 5x < 7 - 2
<=> -5/5 < x < 5/5
<=> -1 < x <1