X-y is positive when y is further away from 0, compared to x. In other words, when y is a larger negative
For example
x = -2
y = -5
x-y = -2-(-5) = -2+5 = 3
Answer:

Step-by-step explanation:
If x is inversely porportionaly to y, then for some constant k,

Since y is 4 when x = 18, k is equal to 4*18=72, so the equation is:

Answer:
Question 1:
a. The answer is B because the graph inclined really quickly and then it inclined at a much slower pace, suggesting that the person was running and then walking.
b. The answer is C because you can see on the graph that after a while, the distance from the starting point goes back to 0, indicating that the person forgot something at home.
Question 2:
a. The dashed line reaches the bottom at 15:30 so the answer is C.
b. Siobhan travels 8 km to go from home to school so the answer is 2 * 8 = 16 which is option D.
Question 3:
The answer is C because after the distance from the starting point increased, it then decreased and came back to the original point suggesting that he walked, turned around and walked back to the starting point.
Answer:
Option C) The value of a is correct, but the value of b is incorrect.
Step-by-step explanation:
z = 8(cos(300°) + isin(300°))
z = 8cos(300°) + 8isin(300°)

So we can see that a = 4 which is correct but b =
and b in the question says it is b
so its incorrect so Option C is your answer.