Undefined as the line is parallel to y axis ie; x=3
Let a and b represent the heights of the corresponding buildings (in meters).
... a = b +271 . . . . . . . a is 271 meters taller than b
... 2b -a = 211 . . . . . . if a is subtracted from twice b, the result is 211
Use the expression for a in the first equation to substitute for a in the second.
... 2b - (b+271) = 211
... b = 482 . . . . . . . . . . . simplify and add 271
... a = b +271 = 753
Building a is 753 meters tall; building b is 482 meters tall.
Answer:

Step-by-step explanation:
Let E be the set of all even positive integers in the universe Z of integers,
i.e
E = {2,4,6,8,10 ....∞}
be the characteristic function of E.
∴

For XE(2)
since x is an element of E (i.e the set of all even numbers)
For XE(-2)
since - 2 is less than 0 , and -2 is not an element of E
For { x ∈ Z: XE(x) = 1}
This can be read as:
x which is and element of Z such that X is also an element of x which is equal to 1.
∴

E = {2,4,6,8,10 ....∞}
40/3 days, (13.33 days)
Step-by-step explanation:
Set up the equation, 15/20 = 10/x, and then use cross mutiply to solve it.
10 * 20 = 15x, x = 200/15 = 40/3
Why?
b/c if each pig eats the same amount of food, then the ratio between the number of pigs and days should remain constant.