C2_W1_Lab01_Neurons_and_Layers why only 1 data point?

a1 = linear_layer(X_train[0].reshape(1,1))

Why is only X_train[0] used, that is only one single point. Don’t we need to use both values of X_train (at least two points) to be able to do regression?

This part of the lab is only concerned with how TensorFlow initializes the weights.

The second paragraph of the notes tells you that the weights are initialized when you first apply the layer.

We’re not trying to do training yet.