a ) ( a x + a y + a z ) : ( x + y + z ) = a × ( x + y + z ) : ( x + y + z ) = a
→ il dau factor comun pe a
b) [ 5a ( a + b ) + 3 ( a + b ) ] : ( a + b ) = 5 a + 3
→ dau factor comun pe ( a + b )
= ( a + b ) × ( 5 a + 3 ) : ( a + b ) =
= 5 a + 3
c) ( a x + 3 x ) : ( a + 3 ) : x = 1
= x ( a + 3 ) : ( a + 3 ) × 1 / x =
= x × 1 / x =
= 1
d) ( 2 a + 3 a - 5 a ) : ( x + y ) = 0
= ( 5 a - 5 a ) : ( x + y ) =
= 0 : ( x + y ) =
= 0