Answer:
The correct answer is first option
(7x + 4)(7x − 4)
Explanation:
Points to remember
Identities
(a + b)(a - b) = a² - b²
It is given an expression,
49x² - 16
To factorize the expression 49x² - 16
We know that 7² = 49 and 4² = 16
Therefore we can write the given expression as,
49x² - 16 = (7x)² - 4²
It is in the form of the above identity,
(7x)² - 4² = (7x + 4)(7x - 4)
The correct answer is first option