<em>θ</em> is given to be in the fourth quadrant (270° < <em>θ</em> < 360°) for which sin(<em>θ</em>) < 0 and cos(<em>θ</em>) > 0. This means
cos²(<em>θ</em>) + sin²(<em>θ</em>) = 1 ==> sin(<em>θ</em>) = -√[1 - cos²(<em>θ</em>)] = -3/5
Now recall the double angle identity for sine:
sin(2<em>θ</em>) = 2 sin(<em>θ</em>) cos(<em>θ</em>)
==> sin(2<em>θ</em>) = 2 (-3/5) (4/5) = -24/25
Answer:
50
Step-by-step explanation:
Adding up 20, 30, 40, 50, 60, 70, 80, we get 350. There are 7 numbers in this set, so divide this 350 by 7. We obtain the mean, 350/7 = 50 (Answer B)
Answer:
x = 12
Step-by-step explanation:
12x = 146 - 2
x = 144 ÷ 12
x = 12
<h3>
answer:</h3>
x = 5
y = -4
<h3>
steps:</h3>
4x + y = 16
multiply 2nd equation by 2
4x + 6y = -4
subtract equations
0 -5y = 20
-5y = 20
y = 20 ÷ -5
y = -4
substitute y = -4 to find the value of x
4x + (-4) = 16
4x - 4 = 16
4x = 20
x = 5
