-3 x -2, multiply signs first: +, remainder: 3x2 repeat 2 3 times and add; 2 + 2 + 2 = 3, remainder: 0
3.141 * 3.141, multiply signs first: +, remainder 3x2 repeat 3.141 3 times and add; 3.141 + 3.141 + 3.141 = 9,432, remainder: 3.141 * 0.141
shift decimal: 3.141 * 1.41, remainder: 3.141 * 1.41
3.141 * 1.41, repeat 3.141 1 times and add: 3.141 = 3.141, remainder: 3.141 * 0.41
shift onto result: 9.432 + 0.3141 = 9.7461, remainder: 3.141 * 0.41
shift decimal: 3.141 * 4.1
repeat 3.141 4 times and add; 12.564, remainder: 3.1410.1
shift onto result: 9.87174
shift decimal: 3.141 1
shift onto result: 10,053764
result: 9,875881
check back with calculator: 3.141 * 3.141 = 9,875881
Multiplication can be represented as a number of additions and shifting the results of substeps over the decimal point