1) For the data in the table, does y vary directly with x? If it does, write an equation for the direct variation. (hint: you need to find the “k” value)
X Y
4 10
10 25
16 40

Question

1) For the data in the table, does y vary directly with x? If it does, write an equation for the direct variation. (hint: you need to find the “k” value)
X             Y
4              10
10            25
16            40

anonymous · Answer

If y varies directly with x....y = kx
We need to find k and see if the equation works for all the data.
Plug in the first set of values and solve for the k
10 = 4k....What do you get for k?

anonymous · Answer

Could you completely work this one out for me? I have about 15 more problems exactly like this and I just need to see it once

anonymous · Answer

10 = 4k 
What do you get for k?

anonymous · Answer

K= $$\frac{ 5 }{ 2 }$$

anonymous · Answer

yes...so we have y = 5/2 x
Does that work for the other 2 data points? yes it does. so that's the equation