Question

Which method is correct for squaring a binomial expression of the form ax + b, where a and b are real numbers and x is a variable?

Answer 1

Squaring the binomial ax+b:

`\begin{gathered} (ax+b)(ax+b)=(ax)\placeholder{⬚}^2+(ax)(b)+(ax)(b)+(b)\placeholder{⬚}^2 \\ (ax+b)(ax+b)=(ax)\placeholder{⬚}^2+2(ax)(b)+(b)\placeholder{⬚}^2 \end{gathered}`

As you can see above to square the given polynomial using the method A you get at the end the formula given in method B.

Then, both methods are correct