At a high school football game jamie buys 6 hot dogs and 4 soft drinks for $13. amy buys 3 hot dogs and 4 soft drinks for $8.50. what is the price of a hot dog?

X=price of a hot dog
y=price of a soft drink
We can suggest the following system of equations:

6x+4y=13
3x+4y=8.50

We solve this system of equations by reduction method.
  6x+4y=13
-(3x+4y=8.5)

   3x=4.5              ⇒x=4.5/3=1.5

the price of a hot dog will be $1.5.

If you want to know the price of a soft drink, you have to find "y".
6x+4y=13

6(1.5)+4y=13
9+4y=13
4y=13-9
4y=4
y=4/4
y=1

The price of a soft drink is $1.

B.the point lies directly on the regression