a)1+3=4+5=9+7=16+9=25
The pattern is that you have to add odd numbers so you can keep getting the answers(Example:1st-+3,2nd-+5,3rd-+7,4th-+9)
b)1+1=2+2=4+3=7+4=11
The pattern is that you have to add #'s 1 to so on so you can keep getting the answers (Example:1st-+1,2nd-+2,3rd-+3,4th-+4,& etc.)