Solve the equation. Write a reason for each step

6. -6 is the answer

Step-by-step explanation:add 10 to -10 and -40 and bring down 5x since -10 and 10 cancel out you have to cross it out and have -30 from -40 +10 and now 5x=-30 you have to divide 5 on each side and that would give you -6

statement #3: proof- ang is congruent to ang ecd : angles are congruent.  

step-by-step explanation:

1: the missing angles in statement #3  

a.) acb  

reason- the reason why the answer is acb is because angle ecd and angle acb are both the same size *that's what the word congruent means this is really simple.  

2: the missing word in reason #3  

c.) vertical  

reason- the reason why the answer is vertical is because the angles in that diagram on figure 2 is slanted, which is vertical, and the e and a both lay on vertical lines. along with the other's, but e and a are the 2 main points you want to focus on. and c is kind of like your starting point, because c is for both angles, not just one.  

i hope that was and understanding.