Step 3: An Algebraic Perspective
Algebraically speaking, we can express any 3-digit number as:
ax+b (where a, and b are integers).
So, suppose we wanted to multiply 2 2-digit numbers. We can express them in polynomial form. Then, by foiling:
(ax+b)(cx+d) = acx2+(ad+bc)x+bd
Read on to see how we take the algebraic multiplication to higher numbers of digits.