Answer:
1.37 * 10^10 years.
Step-by-step explanation:
Billion = 9 zeroes
13.7 billion = 13.7 * 10^9 = 1.37 * 10^10.
Answer:
x = -2
Step-by-step explanation:
- 3 x - 6x = -18x
- 4 - 18x + 9 = 41
9 - 4 = 5
- 18x + 5 = 41
- 18x = 41 - 5
- 18x = 36
36 divided by -18 is -2
Answer:
Step-by-step explanation:
x - 30 = 14 - 3x
4x = 44
x = 11
Let's call the unknown number x
Now let's decrease it by 30, that is x-30
Now let's write out "14 decreased by three times the number", that is 14 - 3x
The problem says these are the same, that is x - 30 = 14 - 3x
We now want to isolate, or solve for, x
Move the x to one side of the equation by adding 3x to both sides
3x + x -30 = 14 - 3x + 3x
4x -30 = 14
Now move the 30 to the right hand side by adding 30 to both sides
4x - 30 + 30 = 14 + 30
4x = 44
Now all we have to do to get x is divide both sides by 4
4x/4 = 44/4
x = 11
Answer:
b
Step-by-step explanation: