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mikaa_toxica13
Identify the factors of 4x^2 + 20x + 25. (4x + 5)(x + 5) (4x − 5)(x − 5) (2x + 5)(2x + 5) (2x − 5)(2x − 5)
What are the factors of x^2 − 81? (x + 9)(x − 9) (x − 9)(x − 9) (x + 3)(x − 27) Prime
The first term, 4x^2 is the square of 2x. The last term, 25, is the square of 5. If the middle term is 2 * 2x * 5, then this is the square of the binomial (2x + 5)^2
For the second problem, you have the difference of two squares. a^2 - b^2 = (a + b)(a - b)