23
because
the pattern is
(5 10) ..1.. (15 20) ..2.. (25 30) ..3..
..1... = 3
..2.. = 13
so ..3.. = 23
2 times (9+7) is correct.
9 + 7 = 16.
16 multiplied by 2 is 32.
Yes it is true! it is true because two different numbers go to the same number, if it was false it would have to be the one number to two different numbers.
Hope that made sense!
I am sorry I can help more but
Google can graph lines if that helps
You just look up graph of a line with your numbers
