Here are two colors:

We can form new colors by making a combination of the two original colors. Move the slider bar to get the different combinations.

Which color below can obtained by mixing Color 1 and Color 2?

Let us explain the connection to linear algebra. We can represent colors in the RGB color model, so each color is a point in , the first coordinate corresponding to red, the second to green, and the third to blue.

We can denote the RGB coordinates for Color 1 and Color 2 by the vectors and in . When we mix Color 1 and Color 2 with ratio r, The mixed color is:

This is a linear combination of Color 1 and Color 2. So we can rephrase the question above as: Which color below lies in the span of Color 1 and Color 2?