There are ALOT of equations that can go through the point (7,4). So, pick a slope. it doesnt matter what it is. just pick a number. let us say you pick 3.
Your equation is now y=3x+b.
now you need to find b in respect to (7,4). plug 7 and 4 into the equation and solve for b. now you have a function that runs through the coordinate (7,4)!
So if it is going completely horizontally, you know that it will begin with the equation y=?. If you use the point (7, 4) then you know that y is 4. Therefore, the answer would be y=4.
