Expand each of the following using suitable identities: ((x + 2y +43) POLYNONIALS -2x + 3y + 211 (in (Ba-76-ot (v) (-2x + 5y 32% 5. Factorise 4r + 9 +162 +12vy - 242 - 16x2 m2 + y2 + 8z? - 2/2 xy + 2 y 48xz Write the following cubes in expanded form: () (99) 9 ((2x+1) (it) (20 - 3) (iv) 7 Evaluate the following using suitable identities: (ii) (102) (1) (998) 8. Factorise each of the following: Sa+b+12a+b+bab (ii) 8a - b - 120 b +6ab (ii) 27 -125a - 135a +225a (iv) 64a - 27b - 1440 b + 1080 1 1 (v) 27p- р 216 4 9. Verify: (i) x + y = (x + y) (x2 - xy + y2) (ii) x'-yº = (x+y)(x++ xy + y) 10. Factorise each of the following: (i) 27y' +125z (ii) 64m - 343 [Hint : See Question 9.] 11. Factorise : 27x + y +z? 9xyz 1 12. Verify that x' + y +z!–3xyz = (x + y + z)[(x - y) + (y - 3)2 + (z - x)] 2 3. If x + y +z=0, show that[r* + y + z = 3xyz.) 14. Without actually calculating the cubes, find the value of each of the following: (-12)+(7)*+(5) (1) (28)+(-15)' +(-13) 5. Give possible expressions for the length and breadth of each of the following rectangles, in which their areas are given: Area : 25a - 35a + 12 Area: 35+ 13-12 (i)