Question

Simplify: (a+2b+3c)2 –(a-2b-3c)2 -6b2-9bc​

Answer 1

Answer:

(2a+4b+6c)–(2a–4b–6c)–6b2–9bc

= –6b2–9bc

Answer 2

Answer:

(2a-3b)(2b+3c)

Step-by-step explanation:

(a+2b+3c)²–(a-2b-3c)² -6b²-9bc​

a²+4b²+9c²+a*2b+2b*3c+3c*a-(a²+4b²+9c²+a*(-2b)+(-2b)*(-3c)+(-3c)*a)-6b²-9bc

a²+4b²+9c²+2ab+6bc+3ac-(a²+4b²+9c²-2ab+6bc-3ac)-6b²-9bc

a²+4b²+9c²+2ab+6bc+3ac-a²-4b²-9c²+2ab-6bc+3ac-6b²-9bc

4ab+6ac-6b²-9bc

2a(2b+3c)-3b(2b+3c)

(2a-3b)(2b+3c)