A certain star is 2.4 x 102 light years from the Earth. One light year is about 5.9 x 1012 miles. How far
1 answer:
Answer:
2.5 x miles
Step-by-step explanation:
We are given that 1 light year ≈ 5.9 x miles so:
- 4.3 x 10² light year · <u>5.9 x </u>
<u> miles </u>
- 1 light year
Multiply 4.3 an 5.9 and round to 2 significant digits then add the exponents:
≈25 x
This is not the scientific notation since the number is not between 0 and 10 so we move the decimal point by 1 place to the left. We then add 1 to the exponent to obtain the final answer:
≈ 2.5 x miles
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It doesn't really matter which x-value goes in which x-value slot in the equation as long as you match up the y-values in the same fashion. But for the sake of convenience, we will call the 2 in the second ordered pair
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and we can change the improper fraction in the numerator into a mixed number for ease of addition.
And here, we can add, since it's made simple for us.
Finally, to get the slope we can complete the fraction by dividing.
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