<span>a) We know that the correct answer will be the square root of 256 since the competition area is a square with an area of 256 meters. And since 10^2 = 100 which is less than 256, the answer has to be greater than 10. And since 20^2 = 400 which is greater than 256, the answer also has to be less than 20. Therefore the answer has to be between 10 and 20.
b) The last digit has to be either a 4 or a 6. The units digit is the only digit that will contribute to the units digit of the square. And 0^2 = 0, 1^2 = 1, 2^2 = 4, 3^2 = 9, 4^2 = 16, 5^2 = 25, 6^2 = 36, 7^2 = 49, 8^2 = 64, 9^2 = 81. Of the 10 possible digits, only the values 4 and 6 have a square that has an units digit of 6.
c) The square root of 256 based up (a) and (b) above has to be either 14, or 16. So the dimensions are either 14x14 meters or 16x16 meters.</span>
Start with

Multiply the whole equation by 2. Since 2 is positive, we don't need to switch the inequality sign:

Subtract 3 from both sides:

Solve first for the solution of the inequalities. This can be done by replacing first the inequalities sign with the equal sign.
x + y = 1
2y = x - 4
The values of x and y from the system of linear equation are 2 and -1. This means that the intersection of the lines should be at point (2, -1).
Substitute 3 to x and determine the value of y from the second inequality.
2y ≥ x - 4
Substituting,
2y ≥ 3 - 4, y ≥ -1/2
Hence, the solution to this item should be the fourth one.
Answer:
The length of the actual train's car is <u>67.5 feet.</u>
Step-by-step explanation:
Given:
The scale of a model train is 1 inch to 13.5 ft.
Now, to get the length of the actual car of the train.
Let the length of actual train's car be 
And, the length of the car of model train = 
<em>According to the scale of the model train, 1 inch is equivalent to 13.5 ft. </em>
<em>Thus, 5 inches is equivalent to </em>
<em />
Now, to get the length of actual train's car using cross multiplication method:

By cross multiplying we get:

Therefore, the length of the actual train's car is 67.5 feet.