Complete question is;
Roger and Rita each drive at a constant speed between Phoenix and San Diego. Each driver’s distance for the same section of the trip is displayed below. Who had a head start, and how many miles was the head start?
A) Rita had a 28-mile head start.
B) Roger had a 26-mile head start.
C) Roger had a 25-mile head start.
D) Rita had a 22-mile head start.
Answer:
A) Rita had a 28-mile head start.
Step-by-step explanation:
Let's assume that Roger travelled a distance of 60 miles
And that;
Rita travelled a distance of 32 miles
We are told that they travelled between Phoenix and San Diego.
Thus, it means that if they have different distances but covered same section of the trip, it means the one with higher distance started before the section of the trip.
Thus, it means that Rita had a head start of Roger since she covered only 32 miles.
Thus;
Rita had a head start of; 60 - 32 = 28 miles
#5 is very nicely and correctly done.
#7 says: "No matter what X may be, this function of it is always 9 more than 1/2 of X .".
That's a very powerful statement. Now you know that if X is ever 2, the function will be 1/2(2)+9 which is 10.
If X is ever zero, the function will be 1/2(0)+9 which is 9. If X is ever a cow, the function will be 1/2 of a cow, plus the number 9. Which makes no sense, but that's what the function says.
So, when X is -8, the function is 1/2 of -8, plus 9. Which is 5 ... the 'f' of -8.
Whatever X happens to be at the moment, just write that number in place of X in the function, and it'll show you the function of what X is.
f(a bazillion) = 1/2(a bazillion) + 9 .
f(a-28) = 1/2(a-28) + 9 (but simplify it)
First one b ≤ 9 good luck
The number could be any multiple of nine that ends in 4 or 9, like 9, 54, 99, 144, etc.
