Question

expand the following (-a+6b-2c)²​

Answer 1

Step-by-step explanation:

Let (b + c) = x

Then (a + b + c)2 = (a + x)2 = a2 + 2ax + x2

= a2 + 2a (b + c) + (b + c)2

= a2 + 2ab + 2ac + (b2 + c2 + 2bc)

= a2 + b2 + c2 + 2ab + 2bc + 2ca

Therefore, (a + b + c)2 = a2 + b2 + c2 + 2ab + 2bc + 2ca

so answer is

a²+36b²+4c²-12ab-24bc+4ac

Answer 2

Answer:

(-a + 6b - 2c)²

using identity (a + b + c)²

= (-a)² + (6b)² + (-2c)² + 2×-a×6b + 2×6b×-2c + 2×-2c×-a

= a² + 36b² + 4c² -12ab -24bc +4ca