How do I find translation 4 right and 5 units down?

You are confused because you haven't learned the basics. "Translation" can mean a lot of things and you need to explain which one you are talking about.

When a priest is put in charge of an area but he resides in a different area, that is called a translation.

When you hear or read something in one language and speak or write it in another language, that is called a translation.

When a part is made for one car but revised to fit in another car, that is called a translation.

When a mathematical formula assumes a start from one point and is rewritten to start from a different point, that is called a translation. It can be done with or without numbers. Without numbers is called geometry, with numbers is called algebra.

I'm guessing you have an equation for a straight line in the form y=mx with slope equal to m. That line passes through the origin. If you want it to pass through some point (j, k) you subtract the numbers:

y - k = m(x - j)

That is called point-slope form and it can be rewritten in other forms when it's convenient. You are given j=4 and k=-5.

y + 5 = m(x - 4) but you are not given m so you can't complete the answer. Maybe I guessed wrong and you are actually talking about something different.