​Let's Look at y=kx

​In this formula the y and x are our values for our graphing coodinates (x,y).

​

​Suppose we are given our k or constant value in the formula:

​​y=2x

Because we know the k or constant value it is easy to graph our points

​

​What if we aren't give the value for k (constant) and we are just given the graph?

​We know that in the graph we have the x and y values for our formula, from our x-axis and our y-axis.

y=kx.

​

​Let's plug the point (1,2) into the formula. 2=k(1)

​- In order to solve we need to move the 1 to get k on one side of the equation.

​

​How do we get k by itslef?

​What if we aren't give the value for k (constant) and we are just given the graph?

​How do we find the consant?

​​Let's plug the point (1,2) into the formula. 2=k(1)

​- In order to solve we need to move the 1 to get k on one side of the equation.

​- Divide 1 on each side of the equation to get k by itslef:

​2/1=k(1)/1

​*This gives us the the formual k=y/x​

2/1=k​

​

​

​What if we aren't give the value for k (constant) and we are just given the graph?

​How do we find the consant?

​- Point (1,2)

​2/1=k(1)/1

2/1=k

k=2​

​

​Use the formula k=y/x to see if points (2,4) and (3,6) equal the same value for k.

​What if we aren't give the value for k (constant) and we are just given the graph?

​How do we find the consant?

​- Point (1,2)

​2/1=k(1)/1

2/1=k

k=2​​

​Use the formula k=y/x to see if points (2,4) and (3,6) equal the same value for k.

​

​k=4/2 k=2

​k=6/3 k=2

​

​*Because k the same value at each point the graph is proportional.

​Great Job!