Which is the equation of a hyperbola with directrices at y = ±2 and foci at (0, 4) and (0, −4)? x squared over 8 minus y squared over 16 equals 1
y squared over 16 minus x squared over 8 equals 1
x squared over 8 minus y squared over 8 equals 1
y squared over 8 minus x squared over 8 equals 1

Lin is writing an equation to model the proportional relationship between y, the total cost in dollars of downloading videos from a website, and x, the number of videos downloaded. she knows that the total cost to download 3 videos was $12. her work to find the equation is shown below. joylin’s work step 1 k= 3/12= 0.25 step 2 y= 0.25x where did joylin make her first error?

Donald has x twenty-dollar bills and 11 ten-dollar bill. how much money does donald have? write your answer as an expression.

10 points? ? +++ me asap gabriella uses the current exchange rate to write the function, h(x), where x is the number of u.s. dollars and h(x) is the number of euros, the european union currency. she checks the rate and finds that h(100) = 7.5. which statement best describes what h(100) = 75 signifies? a) gabriella averages 7.5 u.s. dollars for every 100 euros. b) gabriella averages 100 u.s. dollars for every 25 euros. c) gabriella can exchange 75 u.s. dollars for 100 euros. d) gabriella can exchange 100 u.s. dollars for 75 euros.