The 7-10 split is the ultimate sign of doom for most bowlers. It occurs when the only pins remaining after the first ball are the two on the back corners of the lane. Since a single ball can never hit both, it's the most difficult split in the game. There is no tried and true way to do it. Even the pros usually consider it a lost cause. The only approach is to try to get one pin to bounce around and hit the other.
Determine which of the two pins is the easiest for you to hit based on your normal bowling method.
Aim at one side of that pin. Do not aim for a direct hit that will drive the pin backward.
Roll the ball with a slightly greater speed than normal. With luck, the ball will strike the pin on one side and force it to ricochet off the side or back of the lane. With a good bounce, that pin will bounce or slide over to the other side and knock down the other pin.