How do you multiply #(2b+5a)^2#?

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Answer 1 · 2016-12-21T04:53:34

#4b^2 + 20ab + 25a^2#

We can expand this expression as:

#(2b + 5a)^2 -> (2b + 5a)(2b + 5a)#

Now we can cross multiple the terms in each set of parenthesis:

#(2b + 5a)(2b + 5a) ->#

#(2b*2b) + (2b*5a) + (5a*2b) + (5a*5a) ->#

#4b^2 + 10ab + 10ab + 25a^2#

Next we can add like terms:

#4b^2 + (10 + 10)ab + 25a^2#

#4b^2 + 20ab + 25a^2#