(2,5x-15)+3=x+15

To solve the equation (2,5x-15)+3=x+15, we need to simplify the expression on the left side first.

First, let's simplify (2,5x-15)+3: 2,5x - 15 + 3 = 2,5x - 12

Now, the equation becomes: 2,5x - 12 = x + 15

Next, we will isolate the variable x by collecting x terms on one side of the equation and constants on the other side.

Subtract x from both sides: 2,5x - x - 12 = 15

Simplify the left side: 1,5x - 12 = 15

Now, add 12 to both sides: 1,5x = 27

Finally, divide by 1,5 to solve for x: x = 18

Therefore, the solution to the equation (2,5x-15)+3=x+15 is x = 18.