(a) 3 2. The seventh number in a sequence of numbers is 31 and each number after the first number in the sequence is 4 less than the number immediately preceding it. The 9th number in the sequence is: (b) 43 (c) 39 (d) 47

Which equation and solution can be used to solve this problem? thirteen less than a number is sixteen. 13-n=16: add 13 to both sides. the answer is 29. n+13=16: subtract 13 from both sides. the answer is 3. n+16=13 subtract 13 from both sides. the answer is 3. n-13=16: add 13 to both sides. the answer is 29.

The parabola x = y² - 9 opens: a.)up b.)down c.) right d.)left

8000 + 8800 + 8000 + 8 million + 80 trillion + another a katrillion equals