We put the expressions on the left side of the equations on the left side of the regression statement, and we repeat that procedure with the right side. Here, the left sides are the same, so we don't need to use a list; on the right side, we do use a list. Desmos will solve for the unknowns. Desmos doesn't permit the use of x or y as regression parameters (unknowns), so we'll use x₁ and y₁ instead: