## MP Board Class 8th Maths Solutions Chapter 9 Algebraic Expressions and Identities Ex 9.2

Question 1.

Find the product of the following pairs of monomials.

(i) 4, 7p

(ii) -4p, 7p

(iii) -4p, 7pq

(iv) 4p^{3}, -3p

(v) 4p, 0

Solution:

(i) 4 × 7p = 28p

(ii) -4p × 7p = -28p

(iii) -4p × 7pq = -28p

(iv) 4p^{3} × -3p = -12p^{4}

(v) 4p × 0 = 0

Question 2.

Find the areas of rectangles with the following pairs of monomials as their lengths and breadths respectively.

(p, q); d (10m, 5n); (20x^{2}, 5y^{2}); (4x, 3x^{2}); (3mn, 4np)

Solution:

Question 3.

Complete the table of products.

Solution:

Question 4.

Obtain the volume of rectangular boxes with the following length, breadth and height respectively.

(i) 5a, 3a^{2}, 7a^{4}

(ii) 2p, 4q, 8r

(iii) xy, 2x^{2}y, 2xy^{2}

(iv) a, 2b, 3c

Solution:

Question 5.

Obtain the product of

(i) xy, yz, zx

(ii) a, -a^{2}, a^{2}

(iii) 2, 4y, 8y^{2}, 16y^{3}

(iv) a, 2b, 3c. 6abc

(v) m, – mn, mnp

Solution:

(i) xy × yz × zx = x^{2}y^{2}z^{2}

(ii) a × (-a^{2}) × a^{3} = – a^{6}

(iii) 2 × ^{4}y × 8y^{2} × 16y^{3} = 1024y^{6}

(iv) a × 2b × 3c × 6abc = 36a^{2}b^{2}c^{2}

(v) m × (- mn) × mnp = – m^{3}n^{2}p