Odpowiedź:
4g + x = h | -4g
x = h - 4g
X - 4a = 7b |-X
-4a = 7b - X |/(-4)
a = [tex]\frac{7b-X}{-4}[/tex]
3px = 2r |/3p
x = [tex]\frac{2r}{3p}[/tex]
2p + 3ar = 4 | -2p
3ar = 4 - 2p |/3r
a = [tex]\frac{4-2p}{3r}[/tex]
-3x + 7a = 1 |+3x
7a = 1 + 3x |/7
a = [tex]\frac{1+3x}{7}[/tex]