I would help but I’m not sure how, please do not press that link or else it will track your address! <33
Answer:
39 + 2x
Step-by-step explanation:
-2
Divide each term (-4x = 8 by -4)
Cancel the common factor of -4
x = 8/-4
THEN DIVIDE
x=-2
Answer:
When squaring a fraction, square both numerator AND denominator
Recall the sum identity for cosine:
cos(a + b) = cos(a) cos(b) - sin(a) sin(b)
so that
cos(a + b) = 12/13 cos(a) - 8/17 sin(b)
Since both a and b terminate in the first quadrant, we know that both cos(a) and sin(b) are positive. Then using the Pythagorean identity,
cos²(a) + sin²(a) = 1 ⇒ cos(a) = √(1 - sin²(a)) = 15/17
cos²(b) + sin²(b) = 1 ⇒ sin(b) = √(1 - cos²(b)) = 5/13
Then
cos(a + b) = 12/13 • 15/17 - 8/17 • 5/13 = 140/221
