block method addition

by Mel
(Philippines)

Please help me answer these two problems. thank you.If you can please show the solution and explanation, so I can teach my son. Thank you very much.

1.The sum of 2 numbers is 50. Their difference is 30. What are the 2 numbers? Use the block method.

Zach's Answer:


2. Two numbers have a sum of 450 and a difference of 130. What are the numbers?

Zach's Answer: