Answer:
Option (3).
Step-by-step explanation:
Option (1).
3(x - 1) = x + 2(x + 1) + 1
3x - 3 = x + 2x + 2 + 1
3x - 3 = 3x + 3 [Not True]
Therefore, this equation is not an identity.
Option (2).
x - 4(x + 1) = -3(x + 1) + 1
x - 4x - 4 = -3x - 3 + 1
-3x - 4 = -3x - 2 [Not true]
Therefore, this equation is not an identity.
Option (3).
2x + 3 =
2x + 3 = 2x + 1 + 2
2x + 3 = 2x + 3 [True]
Therefore, this equation is an identity.
Option (4).
3x - 1.5 = 3x + 3 - x - 2
3x - 1.5 = 2x + 1 [Not true]
Therefore, this equation is not an identity.
In solving this problem we can consider Earth to be a sphere. When we have a circle, then we can use this formula to find arc length:
Where:
L= arc length (in this problem it is disance we need to travel)
R = radius of circle (in this problem it is equal to a radius of Earth)
C = angle we need to pass
We are told that two cities lie halfway around the world. If we fly to west this means angle is 180°.
This gives an arc length of:
If we want to fly to north we need to go to 90° northern latidtude and then back to 17° latitude. This means angle is:
C=2*(90-17)=2*73°=146°
This gives an arc length of:
We can see that flying north is shorter. It is shorter by:
12440.71 miles - 10090.8 miles = 2349.91 miles
Answer:
The cost of extracting the first 50 tons of copper is $151,000.
Step-by-step explanation:
Start-up costs of $150,000.
For the 50 tons of cooper.
So
1 thousand dollars.
So
$150,000 + $1,000 = $151,000
The cost of extracting the first 50 tons of copper is $151,000.