45+6×9-90

To solve the expression \( 45 + 6 \times 9 - 90 \), you should follow the order of operations (PEMDAS/BODMAS):

1. Multiplication first: \( 6 \times 9 = 54 \)

2. Substitute back into the expression: \( 45 + 54 - 90 \)

3. Now perform addition and subtraction from left to right:

   • First add: \( 45 + 54 = 99 \)
   • Then subtract: \( 99 - 90 = 9 \)

So, the final answer is \( 9 \).