Expand using suitable identities: (7x + 5)²

Solution:

Given, (7x + 5)²

Using standard identity: (a + b)² = a² + 2ab + b²

Here, a = 7x and b = 5

(7x + 5)² = (7x)² + [2(7x)(5)] + 5²

= 49x² + 70x + 25

✦ Try This: Expand using suitable identities: (5p - 3)²

Given, (5p - 3)²

Using standard identity: (a - b)² = a² - 2ab + b²

Here, a = 5p and b = 3

(5p - 3)² = (5p)² - 2(5p)(3) + (3)²

= 25p² - 30p + 9

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

NCERT Exemplar Class 8 Maths Chapter 7 Problem 85(xiv)

Expand using suitable identities: (7x + 5)²

Summary:

Expanding (7x + 5)² we get, 49x² + 70x + 25

☛ Related Questions:

• Expand using suitable identities: (0.9p - 0.5q)²
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