Answer:
The two numbers are 31 and 11
Step-by-step explanation:
To double-check the answer. 31 + 11 = 42, and 31-11 = 20
Let
s-------> the amount of money Layla deposits
we know that
so
therefore
<u>the answer is</u>
She could deposit
She could deposit
Answer: Either 25.0 or 25 depending on how your teacher wants you to format the answer
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Explanation:
To start off, it probably helps to translate what the question wants.
It states "For the pilot of airplane B, calculate the angle between the lines of sight to the airplane at C and Jenny's airplane [at point A]".
This fairly long, and possibly complex, sentence boils down to "find angle B"
To find angle B, we need to find the length of side 'a' first
Let,
a = x
b = 4.2
c = 5.7
Note how the lowercase letters (a,b,c) are opposite their uppercase counterparts (A,B,C). This is often the conventional way to label triangles. The lowercase letters are usually for the side lengths while the upper case is for the angles.
We have angle A = 120 degrees
Plug these values into the law of cosines formula below. Then solve for x
a^2 = b^2 + c^2 - 2*b*c*cos(A)
x^2 = 4.2^2 + 5.7^2 - 2*4.2*5.7*cos(120)
x^2 = 17.64 + 32.49 - 47.88*cos(120)
x^2 = 17.64 + 32.49 - 47.88*(-0.5)
x^2 = 17.64 + 32.49 + 23.94
x^2 = 74.07
x = sqrt(74.07)
x = 8.60639297266863
x = 8.6064
So side 'a' is roughly 8.6064 kilometers when we round to four decimal places
Now we'll use this to find angle B
Use the law of cosines again, but this time, the formula is slightly altered so that angle B is the focus instead of angle A
Plug in the side lengths (a,b,c). Solve for angle B
b^2 = a^2 + c^2 - 2*a*c*cos(B)
(4.2)^2 = (8.6064)^2 + (5.7)^2 - 2*(8.6064)*(5.7)*cos(B)
17.64 = 74.07012096 + 32.49 - 98.11296*cos(B)
17.64 = 106.56012096 - 98.11296*cos(B)
17.64 - 106.56012096 = 106.56012096 - 98.11296*cos(B)-106.56012096
-88.92012096 = -98.11296*cos(B)
(-88.92012096)/(-98.11296) = (-98.11296*cos(B))/(-98.11296)
0.906303519535034 = cos(B)
cos(B) = 0.906303519535034
arccos(cos(B)) = arccos(0.906303519535034)
B = 25.0005785532867
It's a bit messier this time around, but we get the approximate angle
B = 25.0005785532867
which rounds to
B = 25.0 degrees
when we round to the nearest tenth. We can write "25.0" as simply "25"
Answer:
A vector ⇒ answer D
Step-by-step explanation:
* Lets revise some definition to solve the problem
- <em>Speed = distance ÷ time</em>
∵ Distance has no direction
∴ Speed has no direction
∴ Speed is a scalar quantity ⇒ (magnitude only)
- <em>Velocity = displacement ÷ time</em>
∵ Displacement has direction
∴ Velocity has direction
∴ Velocity has magnitude and direction
∵ Any vector has magnitude and direction
∴ Velocity is a vector quantity
∵ Velocity describes both speed (magnitude) and direction
∴ Velocity is a vector