Question 255476
{{{a^2+4b^2-25c^2+4ab}}} Start with the given expression.



{{{a^2+4ab+4b^2-25c^2}}} Rearrange the terms.



{{{(a+2b)^2-25c^2}}} Factor {{{a^2+4ab+4b^2}}} to get {{{(a+2b)^2}}}



{{{(a+2b+5c)(a+2b-5c)}}} Factor using the difference of squares formula.



So {{{a^2+4b^2-25c^2+4ab}}} completely factors to {{{(a+2b+5c)(a+2b-5c)}}}



In other words {{{a^2+4b^2-25c^2+4ab=(a+2b+5c)(a+2b-5c)}}}