Applying the trig formula: sin a = cos (90 - a)
cos (2x + 8) = sin (x + 37) = cos (90 - x - 37) = cos (53 - x)
Property of the cosine function -->
(
2
x
+
8
)
=
±
(
53
−
x
)
a. 2x + 8 = 53 - x
3x = 45
x
=
15
∘
b. 2x + 8 = - 53 + x
x
=
−
61
∘
For general answers, add
k
360
∘
Check by calculator.
x = 15 --> sin (x + 37) = sin 52 = 0.788
cos (2x + 8) = cos (38) = 0.788. Proved
x = - 61 --> sin (x + 37) = sin (- 24) = - sin 24 = - 0.407
cos (2x + 8) = cos (-122 + 8) = cos (- 114) = - 0.407. Proved
Answer:
Then, it costs $2120 to order 1000 pens and 2000 notebooks.
Step-by-step explanation:
The Students' Union needs to order 1000 pens and 2000 notebooks. The price per pen when buying 1000 of them is 60c. The price per notebook when buying 2000 of them is 76c.
Then the total of money needed to order 1000 pens and 2000 notebooks is:
Total Money = 1000 × 0.60 + 2000 × 0.76 = $2120
Then, it costs $2120 to order 1000 pens and 2000 notebooks.
Answer:
I got 17.7°
Step-by-step explanation:
Since a complimentary angle adds up to 90 degrees, this would be the right answer... does it require a degree symbol?
Answer:
C.
Step-by-step explanation:
A complementary angle is an angle at 90 degrees and is formed by 2 angles.