Question 15
Algebraic ExpressionsMultiply (3x + 5y + 4z) by (2x − 3y + z)
- A.6x2 + xy − 15y2 + 4z2 + 11xz − 7yz
- B.6x2 + 3xy − 15y2 + 4z2 + 11xz − 5yz
- C.6x2 + 3xy − 15y2 + 4z2 + 13xy − 8yz
- D.6x2 + 5xy − 15y2 + 4z2 + 13xy + 6yz
- E.6x2 + xy − 15y2 + 4z2 + 13xy − 7yz.
Show the answer and explanation
Answer: A (6x2 + xy − 15y2 + 4z2 + 11xz − 7yz)
Explanation
Expanding: 6x² − 9xy + 3xz + 10xy − 15y² + 5yz + 8xz − 12yz + 4z². Collecting gives 6x² + xy − 15y² + 4z² + 11xz − 7yz.