13-y. 1 ————=- 17-y. 2

To solve the equation \[ \frac{13 - y}{17 - y} = 2, \] we can start by cross-multiplying to eliminate the fraction: \[ 13 - y = 2(17 - y). \] Expanding the right side: \[ 13 - y = 34 - 2y. \] Next, we'll isolate \( y \) by adding \( 2y \) to both sides and also subtracting 13 from both sides: \[ -y + 2y = 34 - 13, \] which simplifies to: \[ y = 21. \] So the solution to the equation is \[ y = 21. \]