A line and the Sabine River.
Bordering Texas and Louisiana is the Sabine River, the Red River borders Texas and Oklahoma, and between Texas and New Mexico/Mexico is the Rio.
The Red river forms Texas southwest. The Rio Grande forms the southwest border between Texas and Mexico.
It forms the border between Texas and Mexico.
The Red River forms Oklahoma's southern border with Texas.
The Rio Grande
The River that forms a border between Oklahoma and Texas is the Red River. The river was named for the red-bed country of its watershed.
Lake Texoma
The Red River.
Yes, the Rio Grande River is in Texas and forms a part of the border between Texas and Mexico.
the northeast border of Texas is the red river
the red river is the intended answer but technically only the vegetation line on its right bank forms the border the river itself is entirely within Oklahoma everywhere between the Texas panhandle & Arkansas
The Rio Grande flows through part of the Chihuahuan Desert and forms a border between Texas and the country of Mexico.