Which equation does NOT show direct variation?

a y = ½x
b y + 20 = x + 20
c 12y = x
d y = 34x + 2

Question

Which equation does NOT show direct variation?
 	
a	y = ½x
b	y + 20 = x + 20
c	12y = x
d	y = 34x + 2

mathstudent55 · Answer

Direct variation is

y = kx, 

where k is a number.

Solve all the equations for y and see which one does not follow the form y = kx.

jonna2334 · Answer

i tried and i cant find the answer

jonna2334 · Answer

@mathstudent55

jonna2334 · Answer

i will give medal if you can give me an answer

retireed · Answer

If it is not a DIRECT variation it has to be something else.  

Which equation shows an inverse relationship?

jonna2334 · Answer

b?

mathstudent55 · Answer

Let's look at the choices, one by one.

A. y = ½x
Here you have y = kx where k = 1/2
The equation in choice A follows the direct variation form, y = kx.
The answer is not A.
Ok?

jonna2334 · Answer

i said b

mathstudent55 · Answer

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