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2-by-2 Factoring-Method Multiplication Problems (page 68)
1. 27 14 27 7 2 189 2 378 or 14 27
14 9 3 126 3 378
2. 86 28 86 7 4 602 4 2408
3. 57 14 57 7 2 399 2 798
4. 81 48 81 8 6 648 6 3888 or 48 81
48 9 9 432 9 3888
5. 56 29 29 7 8 203 8 1624
6. 83 18 83 6 3 498 3 1494
7. 72 17 17 9 8 153 8 1224
8. 85 42 85 6 7 510 7 3570
9. 33 16 33 8 2 264 2 528 or 16 33
16 11 3 176 3 528
10. 62 77 62 11 7 682 7 4774
11. 45 36 45 6 6 270 6 1620 or 45 36
45 9 4 405 4 1620 or 36 45 36 9 5
324 5 1620 or 36 45 36 5 9 180 9 1620
12. 37 48 37 8 6 296 6 1776
Answers 243
2-by-2 General Multiplication—Anything Goes! (page 70)
1. 53
or
39 (40
1)
40 53 2120
1 53
53
2067
53 (50 3)
39
50 39 1950
3 39
117
2067
2. 81 (80 1)
57
or 57 81 57 9 9
513 9 4617
80 57 4560
1 57
57
4617
3. 73
73 18 73 9 2 657 2 1314 or
18 (9 2) 73 18 73 6 3 438 3 1314