Solve the following equation. Then place the correct number in the box provided.3x + 1 + 5x = 7 +15 + 7x

To solve the equation, we need to simplify both sides and combine like terms.

Starting with the left side of the equation: 3x + 1 + 5x

We can combine the x terms: 3x + 5x = 8x

So the left side simplifies to: 8x + 1

Moving on to the right side of the equation: 7 + 15 + 7x

We can combine the numbers: 7 + 15 = 22

So the right side simplifies to: 22 + 7x

Now we have the simplified equation: 8x + 1 = 22 + 7x

To solve for x, we want to isolate the x term on one side of the equation. We can do this by subtracting 7x from both sides: 8x - 7x + 1 = 22 + 7x - 7x

This simplifies to: x + 1 = 22

To isolate x, we can subtract 1 from both sides: x + 1 - 1 = 22 - 1

This simplifies to: x = 21

So the correct number to place in the box is 21.