Use the “difference of squares” rule to factor the following expression

49-4y^2
my answer is going to be (7-2y)(7-2y)
I wasn't sure if it could of been (7-2y)(7+2y)

Your answer should be (7-2y)(7+2y).

If you multiply the first equation (7-2y)(7-2y) it would equal 49-14y-14y+4y^2. After simplifying it would equal 49-28y+4y^2. The second option multiplies out to 49+14y-14y-4y^2. The 14y's cancel each other. That leaves 49-4y^2. Hope that helps.

Thank You So Much Sam! :)

To factor the expression 49-4y^2 using the difference of squares rule, we need to first identify if it fits the pattern: a^2 - b^2. In this case, a^2 is 49 and b^2 is 4y^2.

The difference of squares rule states that a^2 - b^2 can be factored into (a + b)(a - b).

So, let's apply this rule to the given expression:
49 - 4y^2 = (7)^2 - (2y)^2

Now, we can rewrite it as:
(7 + 2y)(7 - 2y)

Thus, the correct answer is (7 + 2y)(7 - 2y).