
The equation is 
(Subtract
from each side)
(Commutative property:
)
(Additive inverse property:
)
(Additive identity property:
)
Find the Least Common Denominator (LCD) of improper fraction
and
.
Find the Least Common Multiple of 3 and 7.
\Multiples of 3: 
Multiples of 7: 
The least common multiple of 3 and 7 is 21, the LCD is 21.
\Rewrite each fraction using the least common denominator (LCD).
\
and 
Rewrite the subtract using the LCD.
\
(Add:
)

\
Check:
\Substitutive the value
on original equation

\
(Subtract:
)
\
The solution
.