1st step is to find the radius, then substitute into the formula for area of a circle

to find the radius, just halve the diameter
You would divide both sides by 0.75, to get a=-12.
I think this is a one- step equation, but that is the only way I think you can solve it.
This is impossible without getting a never ending decimal somewhere between 1.14 and 1.15.
It's x=-5. It is a vertical line, and vertical lines have a consistent x coordinate. Since it passes through (-5,0), you take the x-coordinate of this point.