Question

7a+(4+5a)=12a+4 use properties and justify each step

Answer 1

7a+(4+5a)=12a+4 

The first step to this is to simplify both sides of the equation.

You have to combine all of the like terms first...
(7x + 5x) + (4) = 12x + 4
12x + 4 = 12x + 4 

Now the second step is to subtract 12x from both sides....
12x + 4 = 12x + 4 
-12x          -12x

4 = 4

Now you will subtract four from both sides and get....

0=0