1. **State the problem:** We have a triangle with angles 95°, 45°, and an unknown angle $u$. We need to find the value of $u$. 2. **Recall the triangle angle sum rule:** The sum of the interior angles of any triangle is always 180°. This means: $$ 95° + 45° + u = 180° $$ 3. **Set up the equation:** $$ u = 180° - 95° - 45° $$ 4. **Calculate the value of $u$:** $$ u = 180° - 140° = 40° $$ 5. **Conclusion:** The value of the unknown angle $u$ is 40°. This is because the sum of all angles in a triangle must be 180°, so subtracting the known angles from 180° gives the missing angle.