Question

Pentru care valori ale necunoscutei x valoarea expresiei
-5(3x+2.2)-2 este negativa
3(0.5x-4)+8.5x este negativa
ajutor va rog dau 15 puncte si coronita

Answer 1

 

$\displaystyle\bf\\a)\\-5(3x+2,\!2)-2<0\\-15x-11-2<0\\-15x-13<0\\-15x<13~~\Big|:(-15)\\\textbf{Se schimba sensul inegalitatii.}\\\boxed{\bf~x>-\frac{13}{15}}\\\\\\b)\\3(0,\!5x-4)+8,\!5x<0\\1,\!5x-12+8,5x<0\\10x-12<0\\10x<12\\\\x<\frac{12}{10}\\\\\boxed{\bf~x<1,\!2}$