Why does the problem equal 1/y^2+9?
after multiplying the second fraction by -1 to make the denominators equal, then adding, and then simplified the y^2 on the top and the y^4 on the bottom you get 1/y^2-81. how does the 81 turn into a 9? and once it is a nine, why don't you simplify it to (y-3)(y+3)?

Amerchant has coffee worth $60 a pound that she wishes to mix with 50 pounds of coffee worth $90 a pound to get a mixture that she will sell for $70 a pound. how many pounds of the & 60 coffee should be used?

Afriend of mine is giving a dinner party. his current wine supply includes 10 bottles of zinfandel, 8 of merlot, and 11 of cabernet (he only drinks red wine), all from different wineries. (a) if he wants to serve 3 bottles of zinfandel and serving order is important, how many ways are there to do this? ways (b) if 6 bottles of wine are to be randomly selected from the 29 for serving, how many ways are there to do this? ways (c) if 6 bottles are randomly selected, how many ways are there to obtain two bottles of each variety? ways (d) if 6 bottles are randomly selected, what is the probability that this results in two bottles of each variety being chosen? (round your answer to three decimal places.) (e) if 6 bottles are randomly selected, what is the probability that all of them are the same variety? (round your answer to three decimal places.)

Whats the theoretical probability of popping a polka dot balloon? express your answer as a fraction, decimal and percent solid 15 polka dot 5 striped 17 plzz me due tomorrow