Answer:
Given that the expression is z+(z+6)
The equivalent expression to the give expression
From the given expression z+ (z+6)
z+ (z+6)
=z+z+6
Adding the like terms
=2z+6
Taking the common term 2 outside of the above expression
=2(z+3)
Therefore z+ (z+6) =2(z+3)
Therefore the other given optional expressions are not equivalent to the given expression.
The option 2(z+3) is correct and it is the equivalent expression.
<u>Hence the given expression z+ (z+6) is equivalent to the expression 2(z+3)</u>
