Selina Concise Class 6 Math Chapter 18 Substitution Exercise 18C Solution
EXERCISE 18C
(1) Fill in the blanks:
(i) 2a + b – c = 2a + (b – c)
Contents
(ii) 3x – z + y = 3x – (z – y)
(iii) 6p – 5x + q = 6p – (5x – q)
(iv) a + b – c + d = a + (b – c + d)
(v) 5a + 4b + 4x – 2c = 4x – (2c – 5a – 4b)
(vi) 7x + 2z + 4y – 3 = – 3 + 4y + (7x + 2z)
(vii) 3m – 2n + 6 = 6 – (2n – 3m)
(viii) 2t + r – p – q + s = 2t + r – (p + q – s)
(2) Insert the bracket as indicated:
(i) x – 2y =- (- x + 2y) = – (2y – x)
(ii) m + n – p = – (- m – n + p) = – (p – m – n)
(iii) a + 4b – 4c = a + (4b – 4c)
(iv) a – 3b + 5c = a – (3b – 5c)
(v) x2 – y2 + z2 = x2 – (y2 – z2)
(vi) m2 + x2 – p2 = – (- m2 – x2 + p2) = – (p2 – m2 – x2)
(vii) 2x – y + 2z =2y – (- 2x + y) = 2z – (y – 2x)
(viii) ab + 2bc – 3ac =2bc – (- ab + 3ac) = 2bc – (3ac – ab)