Multiply (3x + 5y + 4z) by (2x - 3y + z)
A
6x2 + xy - 15y2 + 4z2 + 11xz - 7yz
B
6x2 + 3xy - 15y2 + 4z2
C
6x2 + 3xy - y2 + 4z2
D
6x2 + 3xy - 15y + z2
Verified Correct Answer: A.
Step-by-Step Mathematical Solution
(3x + 5y + 4z)(2x - 3y + z)
6x2 + 9xy + 3x2 + 10xy - 15y2 + 5yz + 8xz - 12yz + 4z2
= 6x2 + xy - 15y2 + 4z2 + 11xz - 7yz
Source: Myschool Past Questions Archive (Record #32655)