2. [tex] \frac{3x}{4*x}= \frac{9}{16} [/tex]
[tex]\frac{3x}{4*x}= \frac{9}{16},x \neq 0[/tex]
[tex] \frac{3}{4}= \frac{9}{16} [/tex]
x∈∅
3. [tex] \frac{2}{5}=0.4 [/tex]
[tex] \frac{7}{10}=0.7 [/tex]
[tex] \frac{1}{5}=0.5 [/tex]
4. [tex] \frac{x}{3}= \frac{y}{5} [/tex]
5x=y*3
5x=3y
5x:5=3y:5
[tex]x= \frac{3}{5}y [/tex],y∈R
10x-4y=30
10x=30+4y
10x:10=30:10+4y:10
[tex]x=3+ \frac{4}{10}y [/tex]
[tex]x=3+ \frac{2}{5}y [/tex],y∈R
