§ 71.025 VEHICLES APPROACHING OR ENTERING INTERSECTION.
   When 2 vehicles approach or enter an intersection from different roadways at approximately the same time, the driver of the vehicle on the left must yield the right-of-way to the vehicle on the right.
(ILCS Ch. 625, Act 5, § 11-901) ('64 Code, § 21-66) Penalty, see § 70.999