+4 Perform the indicated operations and simplify:
1. Add: 7x + 6y + 5z and 4x – 5y + 8z
2. Subtract 4xy + 5yz – 6wz from the sum of 5xy + 4yz + 3wz and 5xy + 6wz – 7yz
3. 3 - 4 + 5
2x−y 2x+y 4x 2−y2
4. √12 + √27 − √75 + √48
