First, tan(<em>θ</em>) = sin(<em>θ</em>) / cos(<em>θ</em>), so if cos(<em>θ</em>) = 3/5 > 0 and tan(<em>θ</em>) < 0, then it follows that sin(<em>θ</em>) < 0.
Recall the Pythagorean identity:
sin²(<em>θ</em>) + cos²(<em>θ</em>) = 1
Then
sin(<em>θ</em>) = -√(1 - cos²(<em>θ</em>)) = -4/5
and so
tan(<em>θ</em>) = (-4/5) / (3/5) = -4/3
The remaining trig ratios are just reciprocals of the ones found already:
sec(<em>θ</em>) = 1/cos(<em>θ</em>) = 5/3
csc(<em>θ</em>) = 1/sin(<em>θ</em>) = -5/4
cot(<em>θ</em>) = 1/tan(<em>θ</em>) = -3/4
9514 1404 393
Answer:
angles (W, X, Y) = (77°, 62°, 41°)
Step-by-step explanation:
<u>Given</u>:
ΔWZY
∠W = 2(∠Y) -5°
∠X = ∠Y +21°
<u>Find</u>:
∠X, ∠Y, ∠W
<u>Solution</u>:
Using angle measures in degrees, we have ...
∠X + ∠Y + ∠Z = 180
(∠Y +21) +∠Y + (2(∠Y) -5) = 180
4(∠Y) +16 = 180 . . . . . simplify
∠Y +4 = 45 . . . . . . . . . divide by 4
∠Y = 41 . . . . . . . . . . . . subtract 4
∠W = 2(41) -5 = 77
∠X = 41 +21 = 62
The angle measures of angles (W, X, Y) are (77°, 62°, 41°), respectively.
Answer:
x=-11
y=-1
Step-by-step explanation:
x=4y-7
2x+9y=-31
2(4y-7)+9y=-31
8y-14+9y=-31
17=-31+14
17y=-17
y=-1
x=4(-1)-7
x=-11
Answer:
C
Step-by-step explanation:
<span>reducible.
hope this helps</span>
