Simplify 20-2x8+3^2

The expression 20-2x8+3^2 can be simplified as follows:

First, we simplify the exponent:
3^2 = 3 * 3 = 9

Next, we perform the multiplication:
2 * 8 = 16

Now, we substitute these simplified values into the expression:
20 - 16 + 9

Simplifying further, we perform the subtraction:
20 - 16 = 4

Finally, we add the last term:
4 + 9 = 13

So, 20-2x8+3^2 simplifies to 13.