Question

[tex]I.Calculati:\\
1.2*|x+7|-|x+7|-|x+7|=?\\
2.-|5-x|+|x-5|=?\\
3.~ \frac{2}{5} *|x+9|-0,4*|x+9|=?\\
4.~0,1|x|-0,9|x|+0,8|x|=?\\[/tex]

Answer 1

[tex]1)2|x+7|-|x+7|-|x+7|=2|x+7|-2|x+7|=0 \\ 2)-|5-x|+|x-5|=|x-5|=|x-5|=0 \\ 3) \frac{2}{5}|x+9|-0,4|x+9|=0,4|x+9|-0,4|x+9|=0 \\ 4)0,1|x|-0,9|x|+0,8|x|=-0,8|x|+0,8|x|=0 \\ \\ Nu~iei~in~considerare~modulele,~considera-le~niste~paranteze, \\ rezultatul~oricum~da~0.[/tex]