Question

ajutatima va rog cu prb asta​

Answer 1

$\bf \huge {}^{7)} \frac{3}{5} \geqslant \frac{x + 1}{35} \geqslant {}^{5)} \frac{3}{7} \\ \\ \bf \huge\frac{21}{35} \geqslant \frac{x + 1}{35} \geqslant \frac{15}{35} | \times 35 \\ \\ \bf \huge 21 \geqslant x + 1 \geqslant 15 | - 1 \\ \\ \bf\huge20 \geqslant x \geqslant 14$

x număr natural

x = { 20 ; 19 ; 18 ; 17 ; 16 ; 15 ; 14 }

Answer 2

Răspuns:

x ∈ {14, 15, 16, 17, 18, 19, 20}.

Explicație pas cu pas:

3/5 ≥ x+1 / 35 ≥ 3/7, x ∈ N

21 ≥ x+1 ≥ 15

14 ≤ x ≤ 20,

x ∈ {14, 15, 16, 17, 18, 19, 20}.