I have pain in my hip which goes down my leg as far as my knee. Please any answers.?

Get it checked. Pain in the hips can often refer down to the knees..You may want to have it checked out with your doc....A simple xray can determine if you have significant arthritis of your hip yours. Other condition such as bursitis can cause similar symptoms and it easy to determine with a physical exam by your doc...
Maybe not the hip. Even though the symptoms are felt in the hip and hip arthritis or hip bursitis is a concern, we can also see this in other settings like: originating from the back and radiating to the thigh from a disc or a muscular site or a facet joint problem or even a ciruculation problem needs to be considered. Each of these can have symptoms felt in the hip region but the hip is not the starter.