16.

17.

18.

19.

13a2b-3ab+ca.

17a2x-6xy-3xy2+9by—abx+88. 20x2y-4bxy+12ax-95cx+81c+5cy.

4x2-2cx2+5y.

8cx-161ab+7.
135abx-95ab+4ax-14.

-2-2c+4d-e+f.

-11c-8x+15cx-9ax.

61ax-24bx-cx-11.

16cx-1266x+8xy.

5x-15by+4cx.

27.

-9-3x+4x+32axy.

28.

168a2+6b2x.

-41+7ab+ax· 9cx. 176abx+63αax +92.

45..

46.

47.

48.

26axy+42ay-ac- ax.

-127a-17b-200ac-33.

-38acx+16abx-18aby+12acy-286.

28ab+9x2-13by.

49.

-4ab.

MISCELLANEOUS EXERCISES.

When x = 1, y = 3, z = 4, a = 5.