Odpowiedź:
[tex]a)\\\\\frac{x}{15}=\frac{4}{3}\\\\3x=4\cdot15\\\\3x=60\ \ |:3\\\\x=20\\\\\\b)\\\\\frac{3-2x}{12}=\frac{3}{2}\\\\2(3-2x)=3\cdot12\\\\6-4x=36\\\\-4x=36-6\\\\-4x=30\ \ |:(-4)\\\\x=-\frac{30}{4}\\\\x=-7\frac{2}{4}\\\\x=-7\frac{1}{2}\\\\\\c)\\\\\frac{6}{2-3x}=\frac{3}{7}\ \ ,\ \ x\neq \frac{2}{3}\\\\6\cdot7=3(2-3x)\\\\42=6-9x\\\\42=6-9x\\\\9x=6-42\\\\9x=-36\ \ |:9\\\\x=-4[/tex]
[tex]d)\\\\\frac{4}{1-x}=\frac{3}{1+x}\ \ ,\ \ x\neq 1\ \ ,\ \ x\neq -1\\\\4(1+x)=3(1-x)\\\\4+4x=3-3x\\\\4x+3x=3-4\\\\7x=-1\ \ |:7\\\\x=-\frac{1}{7}[/tex]
