Answer: y = -4x
Step-by-step explanation: You would use the formula y = mx + b to solve your problem. When you plug the numbers in, you get y = -4x. There would be no "+ b" because in this case, the y-intercept (b) is equal to zero. Therefore, you would not need to write "y = -4x + 0" because that would not be the equation in its simplest form.