add the sum and difference identities for sin x to derive 1/2 [sin(x + y) + sin(x - y)] = sin x cos y

pls refer ro the top for answer

- (2, -7)

- lines r and s and lines t and u must be parallel

60.9774

step-by-step explanation:

because when you add 47.6 plus 7.32 equals 54.92

and when you add .0574 + 6= 6.0574

and when you add 54.92 and 6.0574 you get the answer of 60.9774.

plzz mark brainlest last one got deleted. cause i didn't explain it but i did but i understand what the mod meant