Respuesta :

Notice that:

[tex]\begin{gathered} 100b^2=(10b)^2, \\ 49c^2=(7c)^2\text{.} \end{gathered}[/tex]

Therefore:

[tex]100b^2-49c^2=(10b)^2-(7c)^2=(10b+7c)(10b-7c)\text{.}[/tex]

Answer:

[tex]100b^2-49c^2=(10b+7c)(10b-7c)\text{.}[/tex]