Both of your answers are correct. In the first equation, if you were to substitute 3 for x, because you have to do exponents first, you have 3^2, which is 9, and 9*6 =54. If you were to substitute -3 for x again you would have to do the exponents first which would be -3^2 which is 9, and 9*6 = 54.
For the second question, if I substitute 0.75 for t, I get -9 + 18 + 7. This is equal to 16, and therefore the answer would be D. Hope this helps! :D. Let me know if you have questions about my explanation, and feel free to post more questions.
42 because it is all of the sides have to be added up for the perimeter so the formula would be 14+14+7+7.
Answer:
Her answer is not correct because the sum cannot be less than either addend.
The correct answer is
Step-by-step explanation:
Given:
The expression to add is given as:

Alaina got the answer as 
Let us first try to add the fractions and arrive at the answer.
Taking LCD of 18 and 20, we get LCD = 180
Now, making denominators of each fraction equal to 180 and changing the numerators accordingly.

Therefore, the result of Alaina is not correct because she got an answer which is less than the fraction
. But when we add two fractions, the result must be greater than either of the addend.
Therefore, her answer is not correct because the sum cannot be less than either addend.
Answer: 20,000
Step-by-step explanation:
every 30 years 10,000 adds to the population
30 years=10,000 people
60 years=20,000 people