Answer:
It's B. 20
Step-by-step explanation:
edge 2020
Answer:
Step-by-step explanation:
Required to prove that:
Sin θ(Sec θ + Cosec θ)= tan θ+1
Steps:
Recall sec θ= 1/cos θ and cosec θ=1/sin θ
Substitution into the Left Hand Side gives:
Sin θ(Sec θ + Cosec θ)
= Sin θ(1/cos θ + 1/sinθ )
Expanding the Brackets
=sinθ/cos θ + sinθ/sinθ
=tanθ+1 which is the Right Hand Side as required.
Note that from trigonometry sinθ/cosθ = tan θ
Ducks have 1 head. Dogs have 1 head.
Ducks have 2 feet. Dogs have 4 feet.
If x = no. of ducks and g = no. of dogs
x + g = 25
2x + 4g = 80
Let's use substitution to solve.
x + g = 25 ⇒ x = 25 - g
replace x with 25 - g in the other equation and solve for g
2x + 4g = 80
2(25 - g) + 4g = 80
50 - 2g + 4g = 80
50 + 2g = 80
2g = 30
g = 15
Now use g = 15 in an earlier equation to find x.
x + g = 25
x + 15 = 25
x = 10
Answer:
Step-by-step explanation:
