Respuesta :
using(a+b)^2 = a^2 + 2ab = b^2
so
(3x + 7y)^2
= 9x^2 + 42xy + 49y^2
answer
9x^2 + 42xy + 49y^2
so
(3x + 7y)^2
= 9x^2 + 42xy + 49y^2
answer
9x^2 + 42xy + 49y^2
Answer:
[tex]9x^{2}+42xy+49y^{2}[/tex]
Step-by-step explanation:
we know that
[tex](a+b)^{2}=a^{2}+2ab+b^{2}[/tex]
In this problem we have
[tex](3x+7y)^{2}[/tex]
so
[tex]a=3x[/tex]
[tex]b=7y[/tex]
substitute
[tex](3x+7y)^{2}=(3x)^{2}+2(3x)(7y)+(7y)^{2}[/tex]
[tex]=9x^{2}+42xy+49y^{2}[/tex]