Answer:
A.
Step-by-step explanation:
tan x= 6/8
usually tan θ = perpendicular / base
So,
we get perpendicular = 6, base = 8
Now using Pythagorean Theorem to find hypotenuse
hyp² = base² + Perp²
hyp² = 8² + 6²
hyp²= 64 + 36
hyp²=100
Taking sq root on both sides
hypotenuse = 10
Now
sin θ = Perpendicular / Hyp
sin x = 6 / 10
Now
cos θ = base / Hyp
cos x = 8 / 10
The answer is -4 final answer
Speed = Distance / Time
Distance = Speed*Time
For this problem, we should bear in mind that current speed has an impact on the boat speed...
for upstream, the boat goes against the current, and so its speed is
U = V - C
where V is the speed of the boat
C is the current speed
for downstream, it will be:
D = V + C
Convert the problem into mathematical equations:
4D + 3U = 116
3D + 4U = 108
4(V+C) + 3(V-C) = 116
4V + 4C + 3V -3C =116
7V + C = 116
3(V+C) + 4(V-C) = 108
3V + 3C + 4V - 4C = 108
7V - C = 108
Solving the equations:
7V + C = 116
7V - C = 108
14V = 224
V = 16km/hr —-> speed of boat
to get C:
7(16) + C = 116
C = 4km/hr
Answer: r = 3
Step-by-step explanation:
Step 1: Cross-multiply.
2r = 12/18
(2)*(18)=12*r
36=12r
Step 2: Flip the equation.
12r=36
Step 3: Divide both sides by 12.
12r/12 = 36/12
r = 3