What was done to get from Step 2 to Step 3 in solving the equation? 12x + x = 180 − x

Step 1: 32x =1 80 − x

Step 2: 52x = 180

Step 3: x = 72

Gregory draws a scale drawing of his room. the scale that he uses is 1 cm : 4 ft. on his drawing, the room is 3 centimeters long. which equation can be used to find the actual length of gregory's room?