chloejubilee310 chloejubilee310 23-10-2018 Mathematics contestada Find the product of (3x+7y)^2 A) 9x^2 - 42xy + 49y^2 B) 9x^2 - 49y^2 C) 9x^2 + 49y^2 D) 9x^2+42xy+49y^2