[tex]\displaystyle \\
\texttt{Fractiile echiunitare au numaratorul egal cu numitorul.} \\ \\
a)~ \frac{2x-1}{15}=1 ~~\Rightarrow~~ 2x-1 = 15 ~~\Rightarrow~~ 2x = 16 ~~\Rightarrow~~x = \frac{16}{2}=\boxed{8} \\ \\
b)~ \frac{21}{2x+1}=1~~\Rightarrow~~2x+1=21~~\Rightarrow~~ 2x=20 ~~\Rightarrow~~x= \frac{20}{2} =\boxed{10} \\ \\
c)~ \frac{x+1}{2x} =1~~\Rightarrow~~2x=x+1~~\Rightarrow~~2x-x=1~~\Rightarrow~~x=\boxed{1}[/tex]
[tex]\displaystyle \\
d)~ \frac{5x}{x+8}=1~~\Rightarrow~~5x=x+8~~\Rightarrow~~ 4x=8~~\Rightarrow~~x= \frac{8}{4}=\boxed{2} \\ \\
e)~ \frac{2x+1}{x+4}=1~~\Rightarrow~~2x+1=x+4~~\Rightarrow~~2x-x=4-1~~\Rightarrow~~x=\boxed{3} [/tex]
