You can look at the figure I uploaded to guide you.

Since we are given the value of an angle, it's adjacent side and the hypotenuse is unknown, we can use SOHCAHTOA which means:
Sin(Opposite/Adjacent) Cos(Adjacent/Hypotenuse) Tan(Opposite/Adjacent)

Therefore, with the given values, we will use Cosine.
We will have:
cos(47)= \frac{1000}{x}
x= \frac{1000}{cos(47)}

Taking the value of x by using the calculator, we get 1466.28 m.

Hope that helps. Message me if you have problems, or if there are errors on my answer.