Question

What is the coefficient of the second term of the trinomial?

(4a+5)^2 = 16a^2 + Ba + 25

Answer 1

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Answer 2

Answer: The coefficient of the secong term is 40.

Explanation:

Given polynomial:
`(4a+5)^2`

Here 4a+5 is a binomial and square of a binomial is given by indentity:

`(x+y)^2=x^2+2xy+y^2`

Then,
`(4a+5)^2=(4a)^2+2(4a)(5)+5^2`

`(4a+b)^2=16a^2+40a+25`

On comparing with
`16a^2+Ba+25`, we get B=40

We can see the coefficient of the second term is 40.