Odpowiedź:
Zad. 9
a)
[tex]\frac{4+x}{2}[/tex] - x = 0 /*2
4 + x -2x = 0
-x = -4 /-1
x = 4
b)
[tex]\frac{x-2}{5}[/tex] = [tex]\frac{3+4x}{2}[/tex] /*5
x - 2 = [tex]\frac{15+20x}{2}[/tex] /*2
2x - 4 = 15 + 20x
20x - 2x = 15 +4
18x = 19 /18
x = 19/18 = 1 i 1/18
c) 3 - [tex]\frac{2x+7}{5}[/tex] = 4 /*5
15 - 2x + 7 = 20
-2x = 20 - 15 - 7
-2x = -2 /-2
x = 1
