1. (2x+3)(x+4)
Use foil- first (2x*x), outer (2x*4), inner (3*x), last (3*4):
2x^2 + 8x + 3x + 12
Add like terms:
2x^2 +11x + 12
2. (3x+5)(x-8)
Use foil:
3x^2 - 24x + 5x - 40
Add like terms:
3x^2 - 19x - 40
3. (4c-9)(c^2 +c -7)
Distribute 4c to each term of (c^2 +c -7):
4c^3 + 4c^2 -28c - hold on to this until the end.
Distribute -9 to each term of (c^2 + c -7):
-9c^2 - 9c + 63
Add results, combine like terms:
(4c^3 +4c^2 -28c) + (-9c^2 -9c +63)
B; 4c^3 -5c^2 -37c +63
