sin x = cos 54 = sin (90-54) = sin 46
Hence x = 46 deg
Same technique. Sin 21 = cos (5x+9) = sin (90-5x-9)
81-5x = 21
Or 5x = 60
Or x = 12 deg
hope it helps
Answer:
4 hours, $60
Step-by-step explanation:
Assuming "d" is equal to the dollars Jacob earned and h= hours, you start by setting the equations equal to each other, since both are equal to "d."
15h=10h+20
Subtract 10h from both sides (to combine like terms) so the equation becomes:
5h=20
Divide 5 from both sides, to isolate "d" :
h=4
The number of hours Jacob worked is 4, as the equation above shows. To find the amount of money Jacob made, substitute 4 as "h" into the two original equations:
d= 15(4) d=$60
d=10(4)+20 d=$60
Jacob earned $60 dollars in 4 hours.
Answer:
69
Step-by-step explanation:
to find f(3), we'll have to substitute x with 3
therefore,
f(3) = 19 × 3 + 12
= 57 + 12
= 69
