Respuesta :

Answer:

y=4x+7

Step-by-step explanation:

Let's solve for y.

3y−21=12x

Step 1: Add 21 to both sides.

3y−21+21=12x+21

3y=12x+21

Step 2: Divide both sides by 3.

3y /3 = 12x+21 /3 y=4x+7

brainliest please?