👤

Determinati x € Q oentru care |2x+3|=0,8 (3)

Răspuns :

[tex] |2x + 3| = 0.8(3)[/tex]

[tex] |2x + 3| = \frac{83 - 8}{90} [/tex]

[tex] |2x + 3| = \frac{75}{90} [/tex]

[tex] |2x + 3| = \frac{15}{18} [/tex]

[tex] |2x + 3| = \frac{5}{6} [/tex]

[tex]1)2x + 3 = \frac{5}{6} \: | \times 6[/tex]

[tex]12x + 18 = 5[/tex]

[tex]12x = 5 - 18[/tex]

[tex]12x = - 13[/tex]

[tex]x = - \frac{13}{12}\:\in\:\mathbb{Q} [/tex]

[tex]2) - 2x - 3 = \frac{5}{6} \: | \times 6[/tex]

[tex] - 12x - 18 = 5[/tex]

[tex] - 12x = 5 + 18[/tex]

[tex] - 12x = 23 \: | \times ( - 1)[/tex]

[tex]12x = - 23[/tex]

[tex]x = - \frac{23}{12}\:\in\:\mathbb{Q} [/tex]