Răspuns:
a) I2x-7I=9
2x-7=±9
2x=9+7=>x=16:2=>x=8
2x-7= -9+7=>x=-2:2=>x= -1
_________________
2[3(2x +5 )-4] -4 = 3
2[3(2x +5 )-4] =3+4
3(2x+5)-4=7:2
6x+15=3,5+4
6x=7,5-15
x=-7/5/6=>x=-1,25=>x= (-125/100)⁽²⁵= -5/4
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212x+51-15= 3
212x+36=3
212x=3-36
x= -33/212
