Point of intersection between 2 lines?

Question

I need to find the point of intersection between the following 2 lines:

 

x = 5y-2(1-y)
x = 19

 

please explain how this is done. Thanks.

Answer 1

you know that x= 19 so you already know that the coordinate is going to be (19, y). You have to plug in 19 for x in the first equation so it will come out to be 19=5y-2(1-y) and then solve from then on:

19=5y-2+2y (Distribute the -2)

19=7y-2 (Combine Like-Terms)

21=7y (Add 2 to both sides)

y=3 (Divide both sides by 3)

So, your coordinates will be (19, 3)