Get a Bucket of Water

A straight river $R$ is flowing nearby. Your house $H$ is located on the same side of the river as your piece of land $L$ where you would like to supply a bucket of water taken from the river. Perpendicular distances of your house and piece of land from the flowing river are $d_H$ and $d_L$ units respectively. Perpendicular distance of the lines from $H$ to the river and $L$ to the river is $d_R$