Answer:
1 mile/hr
Step-by-step explanation:
Let the Speed of the boat still in water = a
Speed of the current = b
We know from this formula that speed = distance/time
Hence,
A canoe traveled Downstream with the current and went a distance of 15 miles in three hours.
Downstream = a + b = 15/3
a + b = 5 .........Equation 1
On the return trip, the canoe traveled Upstream against the current. It took 5 hours to make the return trip.
Upstream = a - b = 15/5
a - b = 3 ..............Equation 2
Combining both Equation together
a + b = 5 .........Equation 1
a - b = 3 ..............Equation 2
Subtracting Equation 2 from Equation 1
2b = 2
b = 2/2
b = 1miles/hr
Since b = speed of the current which can also be called rate of the current, the rate of the current = 1 miles/hr
Find Y using the law of cosines:
cos(angle) = adjacent leg / hypotenuse
cos(20) = 11/y
y = 11/ cos(20)
y = 11.706 ( Round answer as needed)
Find X using the law of sines:
Sin(angle) = opposite leg / hypotenuse
Sin(35) = 11.706 / X
X = 11.706 / sin(35)
X = 20.4088 ( Round answer as needed)
Property of addition, because any number added to zero will result as the original number
Answer:
x=3
Step-by-step explanation:
So -11 + 5 = -6, not -16.
Then divide -6 and -2x by -2 and x=3
Answer:
4) 16√3 in²
5) 63 cm²
Step-by-step explanation:
The formula to use in these cases is ...
A = (1/2)ab·sin(θ)
where a, b are the side lengths and θ is the angle between them.
It helps to know the trig functions of the "special" angles used here.
sin(120°) = sin(60°) = (√3)/2
cos(60°) = 1/2
sin(135°) = cos(45°) = (√2)/2
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4) The external angle at the base is the supplement of 120°, so is 60°. Then the length of the missing segment between the end of the base and the right angle at h is ...
x = (8 in)cos(60°) = (8 in)(1/2) = 4 in
So, the bottom edge of the triangle is 12 in - 4 in = 8 in.
The area is ...
A = (1/2)(8 in)(8 in)sin(120°) = (1/2)64(√3)/2 in² = 16√3 in²
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5) As in the previous problem, the difference between the given horizontal dimension and the base of the triangle is ...
x = (18 cm)cos(180°-135°) = 18(√2)/2 cm = 9√2 cm
Then the base of the triangle is ...
16√2 cm -9√2 cm = 7√2 cm
The area is then ...
A = (1/2)(18 cm)(7√2 cm)(√2)/2 = 63 cm²