Algebra proving direct variation

Apphysics

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I am taking AP Physics and these are two of the summer problems, could you please answer.
Show that if x varies directly as y, the y varies directly as x. The second problem is if a varies directly with c and b varies directly as c, show that a+b varies directly as c.


Thank You!
 
I am taking AP Physics and these are two of the summer problems, could you please answer.
Show that if x varies directly as y, the y varies directly as x. The second problem is if a varies directly with c and b varies directly as c, show that a+b varies directly as c.


Thank You!

I do not understand this constraint about "using geometry/trig" - in your title.

Was this constraint included in the problem (your problem statement does not have that constraint).
 
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I am taking AP Physics and these are two of the summer problems, could you please answer.
Show that if x varies directly as y, the y varies directly as x. The second problem is if a varies directly with c and b varies directly as c, show that a+b varies directly as c.


Thank You!

If x varies directly as y → x = k*y (where k is any constant, generally [FONT=MathJax_Main]≠[/FONT][FONT=MathJax_Main]0[/FONT])

Now continue....
 
If x varies directly as y → x = k*y (where k is any constant, generally [FONT=MathJax_Main]≠[/FONT][FONT=MathJax_Main]0[/FONT])

Now continue....


Im sorry the problem does not need trig and geo. I got the part but what about "then y varies as x" how do i show that. It was apart of the same question
 
Im sorry the problem does not need trig and geo. I got the part but what about "then y varies as x" how do i show that. It was apart of the same question

If you did get that part - why did not you tell us first time?

Now express 'y' in terms of 'x' from the equation i.e. y = ?

What do you get? What does it tell you??
 
If you did get that part - why did not you tell us first time?

Now express 'y' in terms of 'x' from the equation i.e. y = ?

What do you get? What does it tell you??

Sorry. I did jot mean to make you upset. The question states "Show that if x varies directly as y, then y varies directly as x". I undersand x=yk, however, how do you prove the then because if you put y in term of k that would be indirect variation.
 
Sorry. I did jot mean to make you upset. The question states "Show that if x varies directly as y, then y varies directly as x". I undersand x=yk, however, how do you prove the then because if you put y in term of k that would be indirect variation.

Now express 'y' in terms of 'x' from the equation i.e. y = ?

What do you get? What does it tell you??
.
 
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