RS Aggarwal Class 8 Math Third Chapter Squares and Square Roots Exercise 3C Solution

RS Aggarwal Class 8 Math Third Chapter Squares and Square Roots Exercise 3C Solution

EXERCISE 3C

Find the value of the following, using the column method:

(1) (23)²

Solution: Given number 23 = 20 + 3

Here, a = 20 and b = 3

a2	2ab	b2
(20)2 = 400	2 × 20 × 3 = 120	(3)2 = 9

∴ (23)² = (400 + 120 + 9) = 529

(2) (35)²

Solution: Given number 35 = 30 + 5

Here, a = 30 and b = 5

a2	2ab	b2
(30)2 = 900	2 × 30 × 5 = 300	(5)2 = 25

∴ (35)² = (900 + 300 + 25) = 1225.

(3) (52)²

Solution: Given number 52 = 50 + 2

Here, a = 50 and b = 2

a2	2ab	b2
(50)2 = 2500	2 × 50 × 2 = 200	(2)2 = 4

∴ (52)² = (2500 + 200 + 4) = 2704.

(4) (96)²

Solution: Given number 96 = 90 + 6

Here, a = 90 and b = 6

a2	2ab	b2
(90)2 = 8100	2 × 90 × 6 = 1080	(6)2 = 36

∴ (23)² = (8100 + 1080 + 36) = 9216.

Find the value of each of the following, using the diagonal method:

(5) (67)²

(6) (86)²

(7) (137)²

(8) (256)²