Answer
$y^2=28x$
Work Step by Step
Standard form of a parabola is given as: $y^2=4px$ ...(1)
Formula to find focus is: $F(p,0)$ and formula to find directrix is: $x=-p$ or, $x+p=0$
As we are given that focus is: $(7,0)$ and directrix is: $x=-7$ or $x+7=0$
Plug all these data in equation (1), we have: $p=7$
Thus, $y^2=4(7)x \implies y^2=28x$
