Write a direct variation equation that relates x to y. Then solve. Show both the equation and the solution. If y = 8 when x = 4, find y when x = 5.

Question

ddcamp · Answer

Direct variation means that there is some number k such that:
y=k*x .

Can you find k given y=8 when x=4?

anonymous · Answer

i dont think so im really new to this could u expain it to me???

ddcamp · Answer

So, we're given an initial condition: "y=8 when x=4," and we're told that we have a direct variation equation. This means that, given x, y=k*x.

We plug the given values for x and y into the equation, giving us:
8=k*4

Can you solve for k?

anonymous · Answer

wait i think ive got it 
y=kx 
8=k * 4 
k=8/4=2 

y=2x 
y=2 * 5 
y=10

anonymous · Answer

right?

ddcamp · Answer

Yes

anonymous · Answer

awesome! thanks so much!