Answer:
c =3.9375 hours
Step-by-step explanation:
The formula to determine time to finish the job together is
1/a + 1/b = 1/c
Where a and b are the times to complete the job separately and c is the time to complete the job when working together
1/7 + 1/9 = 1/c
Multiply by 63c to get rid of the fractions
63c*(1/7 + 1/9) = 1/c *63c
9c + 7c = 63
Combine like terms
16c = 63
Divide each side by 16
16c/16 = 63/16
c =3.9375 hours
Answer:
Here,
(cosθ + sinθ/sinθ) – (cosθ – sinθ/cosθ) = secθ cscθ
Now, Cross Multiplication
(cosθ + sinθ/sinθ) – (cosθ – sinθ/cosθ) = secθ cscθ
cosθ(cosθ + sinθ) – sinθ(cosθ – sinθ)/sinθ cosθ
cos²θ + sinθ cosθ – sinθ cosθ + sin²θ/sinθ cosθ
cos²θ + sin²θ/sinθ cosθ
Here, we know the identity
cos²θ + sin²θ = 1
So,
cos²θ + sin²θ/sinθ cosθ can be written as
1/sinθ cosθ
Here, we also know the identity
1/sinθ = cscθ
1/cosθ = secθ
1/sinθ cosθ can be written as
secθ cscθ
= L.H.S
Hence Proved!!
<u>-TheUnknownScientist</u><u> 72</u>
Expression: (x + 4)/3
Plug in 5 for x
(5 + 4)/ 3 = 9/3 = 3
The solution is 3
Answer:
3 + 2k
Step-by-step explanation:
Given:
1/5(15 + 10k)
= (1/5 * 15) + (1/5 * 10k)
= (1 * 15)/5 + (1 * 10k)/5
= 15/5 + 10k/5
= 3 + 2k
Therefore,
1/5(15 + 10k) = 3 + 2k
The equivalent expression is 3 + 2k
