A day full of math games & activities. Find one near you.

Subtract:
(i) -5y² from y²
(ii) 6xy from -12xy
(iii) (a – b) from (a + b)
(iv) a(b – 5) from b(5 – a)
(v) -m² + 5mn from 4m² – 3mn + 8
(vi) -x² + 10x – 5 from 5x – 10
(vii) 5a² – 7ab + 5b² from 3ab – 2a² – 2b²
(viii) 4pq – 5q² – 3p² from 5p² + 3q² – pq

Solution:

Let us subtract the given algebraic expressions.

(i) - 5y² from y²

= y² - (-5y²)

= y² + 5y²

= 6y²

(ii) 6xy from -12xy

= -12xy - 6xy

= -18xy

(iii) (a - b) from (a + b)

= (a + b) - (a - b)

= a + b - a + b

= 2b

(iv) a(b - 5) from b(5 - a)

= b(5 - a) - a(b - 5)

= 5b - ab - ab +5a

= 5a + 5b - 2ab

(v) - m² + 5mn from 4m² - 3mn + 8

= 4m² - 3mn + 8 - (-m² + 5mn)

= 4m² - 3mn + 8 + m² - 5mn

= 5m² - 8mn + 8

(vi) - x² + 10x - 5 from 5x - 10

= 5x - 10 - (- x² + 10x - 5)

= 5x - 10 + x² - 10x + 5

= x² - 5x - 5

(vii) 5a² - 7ab + 5b² from 3ab - 2a² - 2b²

= 3ab - 2a² - 2b² - (5a² - 7ab + 5b²)

= 3ab - 2a² - 2b² - 5a² + 7ab - 5b²

= 10ab - 7a² - 7b²

(viii) 4pq - 5q² - 3p² from 5p² + 3q² - pq

= 5p² + 3q² - pq - (4pq - 5q² - 3p²)

= 5p² + 3q² - pq - 4pq + 5q² + 3p²

= 8p² + 8q² - 5pq

☛ Check: NCERT Solutions for Class 7 Maths Chapter 12

Video Solution:

Subtract: (i) - 5y² from y²(ii) 6xy from -12xy (iii) (a – b) from (a + b) (iv) a(b – 5) from b(5 – a) (v) -m² + 5mn from 4m² – 3mn + 8 (vi) -x² + 10x – 5 from 5x – 10 (vii) 5a² – 7ab + 5b² from 3ab – 2a² – 2b²(viii) 4pq – 5q² – 3p² from 5p² + 3q² – pq

Maths NCERT Solutions Class 7 Chapter 12 Exercise 12.2 Question 3

Summary:

On subtracting the expressions we get: (i) -5y² from y² = 6y²(ii) 6xy from -12xy = −18xy (iii) (a – b) from (a + b) = 2b (iv) a(b – 5) from b(5 – a) = 5a + 5b − 2ab (v) - m² + 5mn from 4m² – 3mn + 8 = 5m² – 8mn + 8 (vi) -x² + 10x – 5 from 5x – 10 = x² – 5x – 5 (vii) 5a² – 7ab + 5b² from 3ab – 2a² – 2b² = 10ab – 7a² – 7b² (viii) 4pq – 5q² – 3p² from 5p² + 3q² – pq = 8p² + 8q² – 5pq

☛ Related Questions:

Subtract: (i) -5y2 from y2 (ii) 6xy from -12xy (iii) (a – b) from (a + b) (iv) a(b – 5) from b(5 – a) (v) -m2 + 5mn from 4m2 – 3mn + 8 (vi) -x2 + 10x – 5 from 5x – 10 (vii) 5a2 – 7ab + 5b2 from 3ab – 2a2 – 2b2 (viii) 4pq – 5q2 – 3p2 from 5p2 + 3q2 – pq

Subtract: (i) - 5y² from y² (ii) 6xy from -12xy (iii) (a – b) from (a + b) (iv) a(b – 5) from b(5 – a) (v) -m² + 5mn from 4m² – 3mn + 8 (vi) -x² + 10x – 5 from 5x – 10 (vii) 5a² – 7ab + 5b² from 3ab – 2a² – 2b²(viii) 4pq – 5q² – 3p² from 5p² + 3q² – pq

Subtract:
(i) -5y² from y²
(ii) 6xy from -12xy
(iii) (a – b) from (a + b)
(iv) a(b – 5) from b(5 – a)
(v) -m² + 5mn from 4m² – 3mn + 8
(vi) -x² + 10x – 5 from 5x – 10
(vii) 5a² – 7ab + 5b² from 3ab – 2a² – 2b²
(viii) 4pq – 5q² – 3p² from 5p² + 3q² – pq

Subtract: (i) - 5y² from y²(ii) 6xy from -12xy (iii) (a – b) from (a + b) (iv) a(b – 5) from b(5 – a) (v) -m² + 5mn from 4m² – 3mn + 8 (vi) -x² + 10x – 5 from 5x – 10 (vii) 5a² – 7ab + 5b² from 3ab – 2a² – 2b²(viii) 4pq – 5q² – 3p² from 5p² + 3q² – pq