12. 6, 24. 13. 10, 15, 3, 60.
16. The first travels 84 miles. 17. 27,17. 18.

14. 10 shillings. 15. 55, 45.

19. 16, 25, 7, 42. 22. 2560. 23. 27. 875, 1125.

20. 3× 47, 4× 47, 5 × 47.

36, 54.

28. 25.

42,84, 168.

21. 15, 21.

42. a+b; a-b. 43. (a+b)?; (a−b)2. 44.

T. A.

a+b2 a+b2 9

30, 20 yards per minute.

26. 70; 42; 35. 27. 90; 72; 60.

29. 4 miles walking, 3 miles rowing, at first.

24. 21; 11.

28.

12 miles.

20. 33

a-b

a+1

a

34. a,

√2

; ±1, ±

√2

No2

35.

6, -4; 4, -6.

38. 4,

36. 5, 4; 4, 5. 37. 4, 2; 2, 4.

-3; 3, -4. 39. 1, 2; 2, 1. 40. ±4, ±3; ±3, ±4.

2 -1

41. 2, 1; 3, . 42. ±5; ±3. 43. 2, 1, −1, −2; 1, 2, −2, — 1. ვ

-1

−2± √3 ̧ −1± √/13; 1, −2= √3, −17 √13 ̧

2

2

46. 5,

2,

3

3

3'

1

51.

2

a

4

1

1

52. 0, a+b, 1⁄2 (a−b) ± 2 √ {(a+3b) (a−b)} ;

0, a + b, 2 (a−b) = 1⁄2 √ {(a+3b)(a−b)}. 53.x=a÷ † (abc) ; &c.

54. (x+y)(y+≈)(≈+x) = ±abc; &c.

55. 1; 2; ±3.

56.

3' 2 2

7. a®+6a3b+15a4b2+20a3b3 +15a2b1+6ab3 +b6.

9. a6-3a1b2+3a2ba — b®.

10. 1-3x+3x2 — x3.

12. 27-54x + 36x2—8x3.
14. x4-8x3+24x2-32x+16.

15. 16x4-96x3 +216x2+216x+81. 17. 2a1x+12a2x2b2y2+2b1y*.

19. 1-4x2+6xa — 4x6 + x8.

22. 1+2x-x2 - 2x3 + x1.
24. 1-6x+15x2-18x3+9x4.

16. 2a3x3+6axb3y3. 18. 2(5x+10x3 +x3).

20. 1+2x+3x2 + 2x3 + xa.

23. 1+6x+13x2 + 12x3 +4xa. 25. 2(4+23x2 + 16x1).

26. 1+3x+6x2+7x3 +6x1+3x5 +x6. 28. 1+3x-5x3 + 3x3 — 206.

29. 1+9x+33x2 + 63x3 +66x1 +36x5+8x®.

30. 1-9x+36x2-81x3÷108x1 - 81x5 +27x®.

31. 2 (36x+171x3 +144x3). 32. 1-2x+3x2 - x2+2x3 +x®.