Mr. guo is thinking of a number. when he takes the absolute value of his number, he gets 15. what could his number be? is there more than one possible answer?

15 or -15

Step-by-step explanation:

The absolute value of a number can be defined as the distance between number and 0 is same on the number line whether it is the left side of the 0 or right side. It is denoted by |x|.

Example: |6| = 6 and |-6| =6

Hence, absolute value of |15| = 15 and |-15| = 15.

Thus, there can be two numbers 15 and -15 whose absolute value is 15.

linearly: 8560 bacteria

exponentially: approximately 75233 bacteria

step-by-step explanation:

assuming it is not exponential (we would have some really complicated logarithms), let's say it is linear. then, after 5 hours, it increased by 1200 bacteria, so every hour it increases by 240 bacteria. this means that after 19 hours, we get 19 * 240 + 4000 bacteria or 3800 + 760 + 4000 = 7800 + 760 = 8560 bacteria.

because it says round your answer, i will do this exponentially (with a calculator, of course). first, we need to find how much it multiplies by every hour, by taking the 5th root of 52/40 or 13/10. this is approximately 0.167. we still need to add 1 to this, because we are multiplying by that number, not adding that amount of the number. now, we just calculate 4000 * (1.167)^19. use a calculator to get approximately 75232.6, or 75233.

what is the original number? you forgot to add it.