Balance ionic equations in acidic medium,

Cr2O7^2- + H^+ + C2O4^2- --> Cr^3+ + CO2

Cr2O7^2- + 14H^+ + 3C2O4^2- --> 2Cr^3+ + 6CO2 + 7H2O

Check it!!!
To be balanced you must have
1. number of atoms of each element on each side must be the same.
2. the charge must balance.
3. electrons lost by oxidation must = electrons gained by reduction.