Add: (i) 8xy and 3xy (ii) 2xyz, xyz and 6xyz (iii) 2a, 3a and 4b (iv) 3x and 2y (v) 5m, 3n and 4p ( … 5b, – 4b and – 10b (xiii) – 2c,…
Answers:
(i) 8xy + 3xy = 11xy
(ii) 2xyz + xyz + 6xyz = (2 + 1 + 6) xyz = 9xyz
(iii) 2a + 3a + 4b
= (2 + 3) a + 4b
= 5a + 4b
(iv) 3x + 2y = 3x + 2y
(v) 5m + 3n + 4p = 5m + 3n + 4p
(vi) 6a + 3a + 9ab
= (6 + 3) a + 9ab
= 9a + 9ab
(vii) 3p + 4q + 9q
= 3p + (4 + 9)q
= 3p + 13q
(viii) 5ab + 4ba + 6b
= (5 + 4) ab + 6b
= 9ab + 6b
(ix) 50pq + 30pq + 10pr
= (50 + 30). pq + 10 pr
= 80pq + 10pr
(x) (-2y) + (-y) + (-3y)
= – (2 + 1 + 3) y
= -6y
(xi) (-3b) + (-b)
= – (3 + 1)b
= -4b
(xii) 5b + (-4b) + (-10b)
= 5b – (4 + 10)b
= 5b – 14b = -9b
(xiii) (-2c) + (-c) + (-5c)
= – (2 + 1 + 5)c = -8c