Odpowiedź :
Odpowiedź:
1)
1/3(s - 2) = s + 4 | *3
s - 2 =3(s + 4)
s - 2 =3s + 12
s - 3s =12 + 2
- 2s = 14
2s = - 14
s = - 14/2 = - 7
2)
0,3(2r - 3) = 0,2 + 0,9
0,6r - 0,9 = 1,1
0,6r = 1,1 + 0,9 = 2
r = 2 : 0,6 = 2 : 6/10 = 2 * 10/6 = 20/6 = 3 2/6 = 3 1/3
3)
5x(x - 2) + 4 = x(5x - 2)
5x² - 10x + 4 = 5x² - 2x
5x² - 5x² - 10x + 2x = - 4
- 8x = - 4
8x = 4
x = 4/8 = 1/2
Odpowiedź:
[tex]1)\\\\\frac{1}{3}(s-2)=s+4\\\\\frac{1}{3}s-\frac{2}{3}=s+4\ \ /\cdot3\\\\s-2=3s+12\\\\s-3s=12+2\\\\-2s=14\ \ /:(-2)\\\\s=-7\\\\\\2)\\\\0,3(2r-3)=0,2+0,9\\\\0,3r-0,9=1,1\\\\0,3r=1,1+0,9\\\\0,3r=2\ \ /:0,3\\\\r=2:0,3\\\\r=2:\frac{3}{10}\\\\r=2\cdot\frac{10}{3}\\\\r=\frac{20}{3}\\\\r=6\frac{2}{3}[/tex]
[tex]3)\\\\5x(x-2)+4=x(5x-2)\\\\5x^2-10x+4=5x^2-2x\\\\5x^2-10x-5x^2+2x=-4\\\\-8x=-4\ \ /:(-8)\\\\x=\frac{4}{8}\\\\x=\frac{1}{2}[/tex]