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.
Answer: (0, -6)
Step-by-step explanation:
The center is the midpoint of the diameter, meaning that the coordinates of Y must be (0, -6).
Answer:
13
Step-by-step explanation:
For a quadratic of the form

, we have the quadratic formula

,
where a is the coefficient (number before the variable) of the squared term, b is the coefficient of the linear term, and c is the constant term.
So, given

, we can get that

, and

. We substitute these numbers into the quadratic formula above.





This is our final answer.
If you've never seen the quadratic formula, you can derive it by completing the square for the general form of a quadratic. Note that the

symbol (read: plus or minus) represents the two possible distinct solutions, except for zero under the radical, which gives only one solution.
Answer:
#3: 81
Step-by-step explanation:
I haven't done this type of math in a while so I'm unsure about #1 and #2, but #3 is 81.
3^4 = 3 × 3 × 3 × 3
3^4 = 9 × 3 × 3
3^4 = 27 × 3
3^4 = 81