Answer:
60, 75, 90, 105, 120
Step-by-step explanation:
Answer:
He will need 8.34 yards of fabric.
Step-by-step explanation:
Given that,
The length of the fabric, l = 2 2/3 yards = 8/3 yards
The width of the fabric, b = 1 1/2 yards = 3/2 yards
We need to find the piece of fabric Roberto needs. It is equal to the perimeter of the fabric such that,

So, he will need 8.34 yards of fabric.
<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