Find the value of a, if 9a = 76² - 67²

Solution:

Given, 9a = 76² - 67²

Using the Standard identity: a² - b² = (a + b) (a - b)

⇒ 9a = (76 + 67) (76 - 67)

⇒ 9a = 143 × 9

⇒ a = 143

✦ Try This: Find the value of ‘p’, if 4p = 10³ - 6³

Given, 4p = 10³ - 6³

Using the standard identity, a³ - b³ = (a - b) (a² + ab + b²)

⇒ 4p = (10 - 6)(10² + (10)(6) + 6²)

⇒ 4p = (4)(100+ 60 + 36)

⇒ p = 196

☛ Also Check: NCERT Solutions for Class 8 Maths Chapter 9

NCERT Exemplar Class 8 Maths Chapter 7 Problem 114(ii)

Find the value of a, if 9a = 76² - 67²

Summary:

The value of a, if 9a = 76² - 67² is 143

☛ Related Questions:

• Find the value of a, if pqa = (3p + q)² - (3p - q)²
• Find the value of a, if pq²a = (4pq + 3q)² - (4pq - 3q)²
• What should be added to 4c (-a + b + c) to obtain 3a (a + b + c) - 2b (a - b + c)