Answer:
The refrigerator was at around 13 ∘C
Step-by-step explanation:
Newton's Law of Cooling:
The rate of change of a body temperature (amount of heat loss/time of loss) is directly proportional to the difference between its own temperature and the surroundings.
T ⇒ temperature
t ⇒ time
Tenv ⇒refrigerator temperature
⇒ rate of change of he temperature
-h ⇒ constant of proportionality (negative because the temperature is decreasing inside the refrigerator)
We have 3 points:
time (minutes) - Temperature (∘ C)
0 (when the pan was put in the refrigerator) - 46
15 (after 15 minutes) - 27
30 (15 minutes after the first 15 minutes) - 19
= -h (27 - Tenv)
= -h (19 - Tenv)
Now we have a system of two equations and two variables
The refrigerator was at around 13 ∘C
Answer:
∠RST = 120°
Step-by-step explanation:
We assume the positions of the lines and angles will match the attached figure. The angle addition theorem gives a relation that can be solved for x, then for the value of angle RST.
∠RSU +∠UST = ∠RST
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78° + (3x -12)° = (6x +12)° . . . . . substitute given values into the above
54 = 3x . . . . . . . . . . . . . . . . divide by °, subtract 3x+12
108 = 6x . . . . . . . . . . . multiply by 2
120° = (6x +12)° = ∠RST . . . . add 12, show units
The measure of angle RST is 120 degrees.
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<em>Additional comment</em>
Note that we don't actually need to know the value of x (18) in this problem. We only need to know the value of 6x.
The ladder and the outside wall form a right triangle
The length of the ladder is 97.8 feet
<h3>How to determine the
length of the
ladder?</h3>
The given parameters are:
Distance (B) = 22 feet
Angle of elevation (θ) = 77 degrees
The length (L) of the ladder is calculated using the following cosine ratio
cos(θ) = B/L
So, we have:
cos(77) = 22/L
Make L the subject
L = 22/cos(77)
Evaluate the product
L = 97.8
Hence, the length of the ladder is 97.8 feet
Read more about right triangles at:
brainly.com/question/2437195
Answer:
y = -1/2 x - 3.5
Step-by-step explanation:
y = mx+ b
m is the slope of the line
m = -1/2
b is the y-intercept
b = -3.5
Answer:
y = 2.5x
Step-by-step explanation:
y = mx + b
m=2.5 (slope) --> y=2.5x+b
coordinate : (2,5) 2 is the x coordinate, 5 is the y coordinate
to Find b, input the coordinate --> 5 = 2.5(2) + b
5 = 5 + b
0=b
y= 2.5x
This is only since it asked to solve using the point. If you look at the graph, the line intercepts the y-axis at (0,0) so b=0.
hope this helps
