Question 55095
Please help factor completly 49x^2-28xy+4y^2

ans.
given 49x^2-28xy+4y^2
      = (7x)^2-2*(7x)*(2y)+(2y)^2
      = (7x-2y)^2

since( a - b )^2 = a^2-2ab+b^2