Problem: answer this (a+b+c)(a+b+c)?
how many terms do the product contain?
There are six terms in the final answer.
(a + b + c)(a + b + c)
(a*a + a*b + a*c) + (b*a + b*b + b*c) + (c*a + c*b + c*c)
(a^2 + ab + ac) + (ab + b^2 + bc) + (ac + bc + c^2)
Rearrange the terms.
a^2 + ab + ab+ b^2 + bc + bc + c^2 + ac + ac
Combine like terms.
a^2 + 2ab + b^2 + 2bc + c^2 + 2ac