Final answer:
To expand the given equation (3x-7y)(3x+7y), we can use the FOIL method. The final expanded form of the equation is 9x^2 - 49y^2.
Step-by-step explanation:
To expand the given equation (3x-7y)(3x+7y), we can use the FOIL method. FOIL stands for First, Outer, Inner, Last, which represents the order in which we multiply the terms:
First: Multiply the first terms in each parentheses, which gives us (3x)(3x) = 9x^2.
Outer: Multiply the outer terms, which gives us (3x)(7y) = 21xy.
Inner: Multiply the inner terms, which gives us (-7y)(3x) = -21xy.
Last: Multiply the last terms, which gives us (-7y)(7y) = -49y^2.
Adding all these terms together, we get 9x^2 + 21xy - 21xy - 49y^2. The two middle terms (21xy and -21xy) cancel each other out, so our final answer is 9x^2 - 49y^2.