Question

certain algebra sums for class8​

Answer 1

Answer:

Explanation:

. Using suitable algebraic identity, solve 10922

Solution:

Use the algebraic identity: (a + b)² = a² + 2ab + b²

Now, 1092 = 1000 + 92

So, 10922 = (1000 + 92)2

(1000 + 92)2 = ( 1000 )² + 2 × 1000 × 92 + ( 92 )²

= 1000000 + 184000 + 8464

Thus, 10922 = 1192464.

2. Identify the type of expressions:

(i) x2y + xy2

(ii) 564xy

(iii) -8x + 4y

(iv) x2 + x + 7

(iv) xy + yz + zp + px + 9xy

Solution:

(i) x2y + xy2 = Binomial

(ii) 564xy = Monomial

(iii) -8x + 4y = Binomial

(iv) x2 + x + 7 = Trinomial

(iv) xy + yz + zp + px + 9xy = Polynomial

3. Identify terms and their coefficients from the following expressions:

(i) 6x2y2 – 9x2y2z2+ 4z2

(ii) 3xyz – 8y

(iii) 6.1x – 5.9xy + 2.3y

Solution:

(i) 6x2y2 – 9x2y2z2+ 4z2

Terms = 6x2y2, -9x2y2z2, and 4z2

Coefficients = 6, -9, and 4

(ii) 3xyz – 8y

Terms = 3xyz, and -8y

Coefficients = 3, and -8

(iii) 6.1x – 5.9xy + 2.3y

Terms = 6.1x, – 5.9xy, and 2.3y

Coefficients = 6.1, – 5.9 and 2.3

4. Find the area of a square with side 5x2y

Solution:

Given that the side of square = 5x2y

Area of square = side2 = (5x2y)2 = 25x4y2

5. Calculate the area of a rectangle whose length and breadths are given as 3x2y m and 5xy2 m respectively.

Solution:

Given,

Length = 3x2y m

Breadth = 5xy2 m

Area of rectangle = Length × Breadth

= (3x2y × 5xy2) = (3 × 5) × x2y × xy2 = 15x3y3 m2