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Math-John, PhD in Statistics
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Experience:  MS and BS in Math
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is {(-2,-3), (-1,-2), (2,1), (4,-3)} a linear relation. Why

Customer Question

is {(-2,-3), (-1,-2), (2,1), (4,-3)} a linear relation. Why or why not?
is y=-12x-7 a linear relation. Why or why not?
is f(x)=2x^2=5x a linear relation. Why or why not?
Submitted: 2 years ago.
Category: Math Homework
Expert:  Math-John replied 2 years ago.

Hi, welcome to JustAnswer.

 

is {(-2,-3), (-1,-2), (2,1), (4,-3)} a linear relation. Why or why not?

 

No since the first three points are on a straight line but the last one is not on this line. The can be proved by checking the following 3 slopes.

 

1. Point 1 and 2: (-2-(-3))/(-1 -(-2)) = 1 / 1 = 1,

2. Point 1 and 3: (1 - (-3)) / (2 - (-2)) = 4 / 4 = 1.

 

The above shows point 1,2,3 are on the same line.

 

3. Point 1 and 4: (-3-(-3)) / (4-(-2)) = 0.

 

This shows point 4 is not on the line. The following graph shows this.

 

graphic

 

 


is y=-12x-7 a linear relation. Why or why not?

 

Yes since y is a linear function of x.


is f(x)=2x^2=5x a linear relation. Why or why not?

 

 

No since y is a quadratic function of x.

 

Hope this helps and let me know if you have any questions. Thanks.

 

John

Customer: replied 2 years ago.
Would these be linear..
*A population of bacteria triples every hour for 4 hours.
*A taxi service charges a $5 flat fee plus $2 for each kilometre travelled
Expert:  Math-John replied 2 years ago.
1. No, triples means y = c 3^x. It's exponential.

2. Yes since y = 5 + 2x, the fee is linear in mileage.
Math-John, PhD in Statistics
Category: Math Homework
Satisfied Customers: 1303
Experience: MS and BS in Math
Math-John and other Math Homework Specialists are ready to help you
Customer: replied 2 years ago.
Thank you so much! :)
Expert:  Math-John replied 2 years ago.

You are welcome. Glad to help. Feel free to request me by beginning your questions with "For John".

 

John

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