Question

(20+5b-3c)² :- Solve using identities .​

Answer 1

Step-by-step explanation:

Given

(20+5b-3c)²

using (a+b+c)² = a²+b²+c²+2ab+2bc+2ca

so

(20+5b-3c)² = (20)²+(5b)²+(-3c)²+2(20)(5b)+2(5b)(-3c)+2(-3c)(20)

= 400+25b²+9c²+200b-30bc-120c

Answer 2

Answer:

identity

$(a + b + c) {}^{2 } = a {}^{2 +} + b {}^{2} + c {}^{2 +} + 2ab + 2bc + 2ca$

then answer.is

$400 + 25b {}^{2} + 9c {}^{2} + 200b - 30bc - 120c$