The equation of the line on the graph below is a direct variation equation. What is the constant of the variation?

A. 1/4
B. 1/2
C. 3/4
D. 1

The equation of the line on the graph below is a direct variation equation What is the constant of the variation A 14 B 12 C 34 D 1 class=

Respuesta :

The answer is A, 1/4. Hope this helps!

ANSWER


The constant of variation is [tex]\frac{1}{4}[/tex]


EXPLANATION


Method 1

The general equation of a direct variation is of the form;


[tex]y=kx[/tex]


where [tex]k[/tex] is the constant of variation.


We can trace from the diagram that, the points  [tex](-4,-1)[/tex] and [tex](4,1)[/tex] lie on the graph of the direct variation.


This means that any of the above points should satisfy the equation of the direct variation when substituted.

Let us substitute [tex](4,1)[/tex] to obtain;


[tex]1=4k[/tex]


We solve for [tex]k[/tex] to obtain,


[tex]k=\frac{1}{4}[/tex]


Method 2


The constant of the direct variation is the slope of the straight line.

So we can choose any two points on the line, say, [tex](0,0)[/tex] and [tex](1,4)[/tex] and use it to determine the slope.


[tex]Slope=\frac{1-0}{4-0}=\frac{1}{4} [/tex].


Hence the constant of the direct variation is [tex]\frac{1}{4} [/tex].