## ihavemathquestions Determine whether y varies directly with x. If so, find the constant of variation k and write the equation. one year ago one year ago

1. ihavemathquestions

2. ihavemathquestions

3. benzilla

If y varies directly with x, then all the ratios will be the same. Here is an example if y is 2 when x is 1 and y is 4 when x is 2 and y is 6 when x is 3, then this shows direct variation. K=y/x. Now go back and determine if the numbers on your chart vary this way. In my example, you will notice they all vary by 2. If the y value is a same multiple of x for every x and y in your chart, then that is a direct variation.

4. ihavemathquestions

5. max0236

So you have to find the constant variation and write the equation $\frac{ y }{ x } = \frac{ 11 }{ 7 }=\frac{ 13 }{ 8 }=\frac{ 15 }{ 9 }=\frac{ 17 }{ 10 }=?$From what I can see it does not seem to have any variation. for example $\frac{ 6 }{ 3 }=\frac{ 2 }{ 1 }=\frac{ 4 }{ 2 }= \frac{ 12 }{ 6 }=2$ here the y varies directly with x. The constant of variation is 2. The equation is y = 2x.

6. max0236

A linear function written in the form y = kx , where k is not equal to 0 represents direct variation. The slope, k, is constant. The constant, k , is often referred to as the constant of variation. You can write the constant of variation as a ratio y : x . And unless someone else has any ideas I go with no variation that's the best I can do

7. benzilla

Max you are correct. 13/8 does not equal 11/7