Squares Level 30: 4d square mastery (lead 5-9). multiplication window train. 1. Left Edge5123 squared equals 5123 times itself1. Left EdgeUse the highlighted left edge pair.5123times51235x5252 pairs3 pairs4 pairs3 pairs2 pairs3x3Active multiplication train windowraw windowsraw -> 25 | _ | _ | _ | _ | _ | _Use the highlighted left edge pair. Carry waits for settle.2. 2-Pair Window2. 2-Pair WindowAdd both highlighted pairs.5123times51235x5252 pairs103 pairs4 pairs3 pairs2 pairs3x3Active multiplication train windowraw windowsraw -> 25 | 10 | _ | _ | _ | _ | _Add both highlighted pairs. Carry waits for settle.3. 3-Pair Window3. 3-Pair WindowAdd all 3 highlighted pairs.5123times51235x5252 pairs103 pairs214 pairs3 pairs2 pairs3x3Active multiplication train windowraw windowsraw -> 25 | 10 | 21 | _ | _ | _ | _Add all 3 highlighted pairs. Carry waits for settle.4. 4-Pair Center4. 4-Pair CenterAdd all 4 highlighted pairs.5123times51235x5252 pairs103 pairs214 pairs343 pairs2 pairs3x3Active multiplication train windowraw windowsraw -> 25 | 10 | 21 | 34 | _ | _ | _Add all 4 highlighted pairs. Carry waits for settle.5. 3-Pair Right Window5. 3-Pair Right WindowAdd all 3 highlighted pairs.5123times51235x5252 pairs103 pairs214 pairs343 pairs102 pairs3x3Active multiplication train windowraw windowsraw -> 25 | 10 | 21 | 34 | 10 | _ | _Add all 3 highlighted pairs. Carry waits for settle.6. 2-Pair Right Window6. 2-Pair Right WindowAdd both highlighted pairs.5123times51235x5252 pairs103 pairs214 pairs343 pairs102 pairs123x3Active multiplication train windowraw windowsraw -> 25 | 10 | 21 | 34 | 10 | 12 | _Add both highlighted pairs. Carry waits for settle.7. 1-Pair Right Edge7. 1-Pair Right EdgeUse the highlighted right edge pair.5123times51235x5252 pairs103 pairs214 pairs343 pairs102 pairs123x39Active multiplication train windowraw windowsraw -> 25 | 10 | 21 | 34 | 10 | 12 | 9Use the highlighted right edge pair.8. Settle strip8. Settle stripSettle once.Keep ones; carry moves left.raw windows25 | 10 | 21 | 34 | 10 | 12 | 9settled strip26 | 2 | 4 | 5 | 1 | 2 | 9Final multiplication answer25 | 10 | 21 | 34 | 10 | 12 | 9 -> 26245129.