Factories:
16a2 – 144
We have,
= (4a)2 – (12)2
By using the formula a2 – b2 = (a + b)(a – b)
We get,
16a2 – 144 = (4a)2 – (12)2
= (4a + 12)(4a – 12)
= 4(a + 3) 4(a – 3)
= 16(a + 3)(a – 3)