Question

calcular

a) ×-2≤6
b) 2×-13<-×
c)3×-3+2×≤7
d)9×+16<12+4×
e)2×-4<4×+6
f)5×-2≤1×+8

Answer 1

a)
$x - 2 \leqslant 6 \\ x \leqslant 6 + 2 \\ x \leqslant 8$

b)
$2x - 13 < - x \\ 2x + x < 13 \\ 3x < 13 \\ x < \frac{13}{3}$

c)
$3x - 3 + 2x \leqslant 7 \\ 5x \leqslant 7 + 3 \\ 5x \leqslant 10 \\ x \leqslant 10 \div 5 \\ x \leqslant 2$

d)
$9x + 16 < 12 + 4x \\ 9x - 4x < 12 -16 \\ 5x < - 4 \\ x < \frac{ - 4}{5}$

e)
$2x - 4 < 4x + 6 \\ - 4 - 6 < 4x - 2x \\ - 10 < 2x \\ x > \frac{ - 10}{2} \\ x > - 5$

f)
$5x - 2 \leqslant x + 8 \\ 5x - x \leqslant 8 + 2 \\4x \leqslant 10 \\ x \leqslant \frac{10}{4} \\ x \leqslant \frac{5}{2}$

Answer 2

Oi

a) x - 2 ≤ 6

x ≤ 6 + 2

x ≤ 8

b) 2x - 13 < - x

2x + x < 13

3x < 13

x < 13/3

c) 3x - 3 + 2x ≤ 7

3x + 2x ≤ 7 + 3

5x ≤ 10

x ≤ 10/5

x ≤ 2

d) 9x + 16 < 12 + 4x

9x - 4x < 12 - 16

5x < - 4

x < - 4 /5

e) 2x - 4 < 4x + 6

2x - 4x < 6 + 4

- 2x < 10 ==> (× por - 1)

2x > - 10

x > - 10/2

x > - 5

f) 5x - 2 ≤ 1x + 8

5x - 1x ≤ 8 + 2

4x  ≤ 10

x ≤ 10/4 ÷ 2

x ≤ 5/2

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