16x² - 49
= (4x)² - 7²
Identity =》 a² - b² = (a + b) (a - b)
(4x)² - 7²
= (4x + 7) (4x - 7) [3rd option]
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Hope it helps ⚜
You start at 0 on the unit circle the cos of 0 =1, but at cos 0 there is no angle at all so there is no y value so at cos 0 y=0, 180 is the opposite direction of the starting point which is 0 so the x value of cos180= -1 but there is still no upward or downward angle ie.. y value. so the y value = 0 at 0 and 180. answer is 0
B is the answer your welcome