Answer:
The difference of squares is (a - b)(a + b) = a² - b². Since a = x and b = 2, the answer is x² - 4.
Answer:
(2,-4)
Step-by-step explanation
When you reflect a point across the x-axis, the x-coordinate remains the same, but the y-coordinate is transformed into its opposite (its sign is changed). If you forget the rules for reflections when graphing, simply fold your paper along the x-axis (the line of reflection) to see where the new figure will be located.
So.. checking the picture below
we can say y = y, or just do a substitution and end up with

once you know, how long is "x", then you can simply use the cosine of 72° to get "r"
thus