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# Linear functions word problem: fuel

Sal is given a verbal description of a real-world relationship involving a truck's fuel consumption, and is asked to draw the graph that represents this relationship.

## Want to join the conversation?

• What are Linear functions?
• A linear function is when, in its simplest form, there are no variables with exponents greater than 1. A linear function will result in a straight line on a graph that has a slope and a y-intercept. It can be defined by y = ax + b where a is the slope and b is the y-intercept. I hope this helped you.
• What will be my x intercept and y intercept if the question says that the line passes through the points (-3,7) and (5,-1)?
• Find the slope of the line using the formula m=(y2-y1)/(x2-x1). Find the equation of the line with the formula y-y1=m(x-x1).
To find the x-intercept, put 0 in place of y in the equation and solve it.
To find the y-intercept, put 0 in place of x in the equation and solve it.
So in your case, m=(-1-7)/(5+3) = -8/8 = -1
Equation: y-7 = -x-3
=> x+y-4=0
=> x=4, y=4
Hope this helped
• This is like my 4th time watching this. I have no idea what we're doing. This is why I hate home-school because nobody is here to help me in real life. I'm getting so frustrated to the point where I want to cry. Whenever someone tries to explain it to me I have trouble reading what they're telling me and all of the words get mixed around to the point where I give up reading. I don't want to do this anymore. Everyone seems to think it's so easy.
• It can be difficult, but there are people here to help. Can you tell us a little more about where you are getting stuck with the video?
• i am confused i dont get y
• I don't understand anything about this! Can someone help?
• Enrique is driving to Texas. he travels at 70 kilometers per hour for 2 hours, and 63 kilometers per hour for 5 hours. over the 7 hour time period what was Enrique's average speed?

can someone please explain to me this problem.
• you need to add 70+70+63+63+63+63+63, then divide it by 7, because you have to get the total number of km traveled, then divide it by the hours.
• The video simplified:
Karl started off with 400 liters of fuel
so we plot that point(0,400).

Then we multiply 0.8 by 100 and get 80.
subtract the 80 from 400 and we get 320.
Then we plot (100,320).
• sals problem: if dan drives 3 miles in 3 hours how fast is dan driving?

my problem:
Timmy drives to antarctica and drives 34567899765 miles in 78 hours

and he also ate 7 apples during his trip, if he eats 7702823 apples on his next trip how many miles did he go and what was his speed
• Let’s first find out how many miles Timmy drives per apple.

In the first trip, he drove 34,567,899,765 miles and ate 7 apples. So, the miles per apple is:

Miles per apple= total miles/ total apples​=34567899765/7​

which means he drove 4,938,271,395 miles per apple.

Next, if he eats 7,702,823 apples on his next trip, the total miles he drives can be calculated by multiplying the miles per apple by the total number of apples:

Total miles= miles per apple x total apples

Which means he drove 38,019,263,202,282,785 miles.

Finally, if the duration of his next trip is the same as his first trip (78 hours), his speed can be calculated by dividing the total miles by the total hours:

Speed= total miles / total hours

Which means that he was driving at a speed of approximately 487,938,502,593,881 miles per hour.

He must be Lightning McQueen at that speed!

So there's your answer! He drove 38,019,263,202,282,785 miles at a speed of approximately 487,938,502,593,881 miles per hour!

Please note that this is a hypothetical scenario, and the actual distance and speed would depend on many factors such as the route taken, the vehicle used, the driving conditions, etc.

Also, eating apples doesn’t directly correlate with the distance driven. This is just a fun way to look at the numbers.

Happy Learning!

Angelina