1+4=5 2+5=12 3+6=21 8+11= WHAT

Answer 1

So let’s look a little closer into this problem, from the way that each answer is given it looks like the second number in the addition problem is multiplied by the first and then added together into a sum, such as:

1. 1 + [4x1] = 5
2. 2 + [5x2] = 12
3. 3 + [6x3] = 21

If we continue this same pattern for the last problem it would look like this:

8 + [11x8] = 86

Let me know if you have any other questions or need a further explanation. You’ve got this!