Sky Kim

Question number 6 from the Parabola chapter

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Hi, Mike! Can you explain the second way we can approach question number 6 from the Parabola chapter? (The two points where the higher y-coordinate is also farther from the line of symmetry.) It would be great if you can provide an example. Thank you.

Robin

Parabola D in the xy-plane has equation x – 2y^2 – 8y – 11 = 0…

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Parabola D in the xy-plane has equation x – 2y^2 – 8y – 11 = 0. Which equation shows the x-intercept(s) of the parabola as constants or coefficients?

A) x = 2y^2 + 8y + 11
B) x = 2(y + 2)^2 + 3
C) x – 3 = 2(y + 2)^2
D) y = – √(x – 3)/2 – 2

The answer is A) which makes me think this is really just a “do you know the definition of this term” kind of question (similar to official practice test 4.4.28). Can you explain for those weak in this? TIA!

Lena

A video store rents, on average, 240 videos a day for $2.00 each…

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A video store rents, on average, 240 videos a day for $2.00 each. The store determined that for every $0.25 that it increases the rental fee, the number of daily rentals will decrease by 10. This relationship can be represented by
y=(240-10n)(2+0.25n)
where y is the daily income in dollars from video rentals and n is the number of $0.25 increases. Based on this relationship, at what rental fee per video will the store have its highest daily income?
A)$2
B)$4
C)$4.25
D)$7.75
E)$8
SAT2 question:)