The Monongahala River (i'm not quite sure i spelled that right), and the Allegheny River
Source is the Allegheny River and secondary source is the Monongahela River.
The Allegheny River and the Monongahela River
Wabash River
Two rivers that join the Mississippi River are the Missouri River and the Ohio River.
The confluence of the Alleghaney and Monogahela Rivers form the Ohio River at Point State Park in Pittsburgh. Thus the three rivers that "come together" at that point are the Ohio, Allegahaney and Monogahela.
The Allegheny and Monogahela rivers joinb at Pittsburgh to form the Ohio River.
the Ohio,Missouri,Arkansas, and the red river
Allegheny River (from the North East) and the Monongahela River (from the South East) meet to form the Ohio River.
The Allegheny and Monogahela rivers join at the confluence to form the Ohio River.
Ohio, Monongahela and Allegheny
The river that is formed where the Allegheny and Monongahela meet is the Ohio
The two rivers that form the Ohio River are the Alleghenyand Monongahela rivers.
Delaware, Susquehanna, and Ohio river system.
Western Pennsylvania, where the Allegheny and Monongahela rivers join to form the Ohio River.
The Monongahela and Allegheny Rivers join in Pittsburgh to form the Ohio River. Heinz Field is located along where the Allegheny reaches the Ohio.