Answer: 
Step-by-step explanation:
By definition scientific notation has the following form:

Where a is a number between 1 and 10 but not including 10, and the exponent b is an integer.
The decimal point must be after the first digit.
Therefore, keeping the information above on mind, you can write the number as following:

Answer:
x is a variable its value can be changed
Answer:
5/4
Step-by-step explanation:
hope this helps ;)
Answer:
b) ±2
Step-by-step explanation:
3x² = 12
divide each side by 3 to get:
x² = 4
x = ±2