9-4x=3x-40

To solve the equation \(9 - 4x = 3x - 40\), follow these steps:

1. Get all the terms involving \(x\) on one side and the constant terms on the other side. Add \(4x\) to both sides:

   \[ 9 = 3x + 4x - 40 \]

   This simplifies to:

   \[ 9 = 7x - 40 \]

2. Add \(40\) to both sides to isolate the term with \(x\):

   \[ 9 + 40 = 7x \]

   Which simplifies to:

   \[ 49 = 7x \]

3. Divide both sides by \(7\) to solve for \(x\):

   \[ x = \frac{49}{7} \]

   This simplifies to:

   \[ x = 7 \]

So the solution to the equation \(9 - 4x = 3x - 40\) is \(x = 7\).