prosze o pomoc szybko

Odpowiedź:
[tex] \frac{1}{7} x + \frac{2}{7} = 9 \\ \frac{1}{7} x = 9 - \frac{2}{7} \\ \frac{1}{7} x = 8 \frac{5}{7} \: \: \: | \div \frac{1}{7} \\ x = \frac{61}{7} \times 7 \\ x = 61[/tex]
[tex] \frac{2x + 3}{5} = \frac{2 - x}{3} - x \: \: \: | \times 15 \\ 3(2x + 3) = 5(2 - x) - 15x \\ 6x + 9 = 10 - 5x - 15x \\ 6x + 5x + 15x = 10 - 9 \\ 26x = 1 \: \: \: | \div 26 \\ x = \frac{1}{26} [/tex]
[tex]0.2x + 0.3 = - 0.5 \\ 0.2x = - 0.5 - 0.3 \\ 0.2x = - 0.8 \: \: \: | \div 0.2 \\ x = - 4[/tex]
Odpowiedź:
a)
1/7x + 2/7 = 9
1/7x = 9 - 2/7 /*7
x = 7 * 8 5/7 = 7 * 61/7 = 61
b)
(2x + 3)/5 = (2 - x)/3 - x
2/5x + 3/5 = 2/3 - 1/3x - x
2/5x + 1 1/3x = 2/3 - 3/5
6/15x + 1 5/15x = 10/15 - 9/15
1 11/15x = 1/15
26/15x = 1/15 /*15/26
x = 1/15 * 15/26 = 1/26
c)
0,2x + 0,3 = -0,5
0,2x = -0,5 - 0,3 /:0,2
x = -0,8/0,2 = -4
Szczegółowe wyjaśnienie: