Emory used these steps to solve the equation.
x + 7 = 3x + (−5).
1. Add 1 negative x-tile to both sides and create zero pairs.
2. Add 7 negative unit tiles to both sides and create zero pairs.
3. Divide the 12 negative unit tiles evenly among the 2 x-tiles.
4. The solution is x = −6.
Where did Emory make an error?
In step 1, he should have added 3 negative x-tiles to both sides.
In step 2, he should have added 5 positive unit tiles to both sides.
In step 3, he did not divide the tiles evenly.
In step 4, he should have found the solution x = 3.