Chapter 6.2 Solution West Bengal Board : Class 7 Mathematics
West Bengal Board Class 7 Math Solution full Exercise 6.2 by Experts. Here in this page WB Board Class 7 Student can find Ganit Prabha Class 7 Math Chapter 6 বীজগাণিতিক প্ৰক্ৰিয়া (Algebraic Process) Exercise 6.2 Solution.
Board | WB Board |
Class | 7 (Seven) |
Subject | Mathematics |
Book Name | Ganit Prabha |
Chapter | 6 |
Chapter Page Number on Book | 94 and 95 |
Exercise Number | 6.2 |
(1)
(i) 5x+3x
= 8x
(ii) 9y -3y
= 6y
(iii) -4y + 7y
= 3y
(iv) -10 x – 2x
= -12x
(v) 3a + 4a -2a
= 5a
(vi) -7x – 2x +5x
= – 4x
(vii) 6p -2p + 3p
= 7p
(viii) 4x2 – 2x2 -3x2 + x2
= 2x2 – 3x2 + x2
= 0
(ix) 5a2b – 2a2b – 3a2b + 8a2b
= 3a2b– 3a2b + 8a2b
= 8a2b
(x) 3x2 – 6x2 – 2x2 – x2 + 6x2
= – 3x2 – 3x2+ 6x2
=- 6x2+ 6x2
= 0
(3)
(i) 3a + b; 2a + 4b; 5a – b
= 3a + b + 21a 4b + 5a – b
= 10a + 4b
(ii) 5a – 4 + 2a + 3 + 2a – 3
= 9a – 4 + 3 – 3
= 9a – 4
(iii) 6a2 +7a +3 + 9a2 – 2a + 7 + 4a2-2a + 9
= 19a2 + 3a + 19
(iv) 2a2b + 5b2a + 7 + 3a2b – 2b2a + 6 + 8a2b – b2a + 9
= 13 a2b + 2b2a + 22
(v) 4xy + 5x + 7y – 4xy – y – 3x + 3xy – 3y + 2x
= 3xy + 3y
(4)
(i) (8x +6y) – (2x +3y)
= 8x + 6y – 2x – 3y
= 6x + 3y
(ii) ( -3m2 + 2m+ 2) – ( m2 – 2)
= -3m2 + 2m+ 2 – m2 – 2
= -4m2 + 2m + 4
(iii) (2x + 3y) – (8x + 4y + 7)
= 2x + 3y – 8x – 4y – 7
= – 6x – y – 7
(iv) (-9a2 + 3a + 2) – (5a2+ 2a – 1)
= -9a2 + 3a + 2 – 5a2+ 2a – 1
= -14a2 + a + 3
(v) x – (-2x2 + 3y2)
= x + 2x2 + 3y2
(vi) (3x2 + 5xy) – (2x + xy + 3y2)
= 3x2 + 5xy – 2x + xy + 3y2
= x2 + 4xy – 3y2
(5)
(a) 17x2y – 3xy2 + 14x2y + 2xy2
= 31x2y – xy2
(b) -5b + 18a + 6b – 2a
= b + 16a
(c) 4m2 + 3n2 – (6m2 + 7n2)
= 4m2 + 3n2 –6m2 + 7n2
= -2 m2 – 4n2
(d) a- b – (a-b)
= a – b – b + a
= 2a – 2b
(e) (6p – 4q+2r) + (2p + 3q – 4r)
= 6p – 4q + 2r + 2p + 3q – 4r
= 8p – q – 2r
(f) –x +y + z – 2x + 3y – 2
= – 3x + 4y
(g) (x2 + 2x -5) + (3x2 – 8x + 5)
= x2 + 2x -5 + 3x2 – 8x + 5
= 4x2 – 6x
(h) (7x2 – 3x + 3) – (2x2 – 13x – 7)
= 7x2 – 3x + 3 – 2x2 – 13x – 7
= 5x2 + 10x + 10
(i) 6a – 2b – ab – (3a + b –ab) + 2ab – b + a
= 6a – 2b – ab – 3a + b –ab + 2ab – b + a
= 4a – 4b + 2ab
(9) (-11x -7y -9z) – (-7x+3y-5z)
= -11x -7y – 9z + 7x – 3y + 5z
= – 4x – 10y – 4z
(10) (3×2+4x) + (5x2-x)
= 3x2 + 4x + 5x2 – x
= 8x2 + 3x
∴ (8x2 + 3x) – (3x – 5x2)
= 8x2 + 3x – 3x + 5x2
= 13x2
(11) (5 + 9x) + (6 – 7x + 4x2)
= 5 + 9x + 6- 7x + 4x2
= 4x2 + 2x + 11
∴ (x2 – 9x) + (2x2 + 3x + 5)
= x2 – 9x + 2x2 + 3x + 5
= – x2 – 6x + 5
∴ (4x2 + 2x + 11) – (- x2 – 6x + 5)
= 4x2 + 2x + 11+ x2 + 6x – 5
= 5 x2 + 8x + 6