9. All Real numbers
10. x = -12
11. x = 58 / 7, or x = 8.285714... with all digits repeating
12. x = -9
13. x = 73 / 19, or x = 3.842105263157894736... with all 18 of those digits repeating. If you're going to use a decimal, you have to carry it out all the way until it ends or repeats.
14. x = 25 / 81, or x = 0.308641975... repeating (I think). Decimals recommended for entertainment purposes only.
16. x = 19 - 4y
18a. x = hours for assistant; x - 2 = hours for master
18b. 50x = bricks for assistant; 80(x - 2) = bricks for master
18c. Assistant has worked 5 1/3 hours ("five and one third"), master has worked 3 1/3 hours.
18d. No. It will take 8.92 hours to lay 1000 bricks, or you could say that after 8 hours they will have laid 880 bricks.
It said in the instructions that you could round off answers to two decimal places. Is that okay?
ReplyDeleteAnd also, for #18 doesn't the master start work two hours after the assistant so that would be 3 1/3? And I won't round decimals on the test, but can I count it for the homework?
ReplyDeleteOn 18c, wouldn't the master have worked for 3 1/3 hours, not 2 1/3? Since he worked for 2 hours less?
ReplyDeleteYes, it's 3 1/3, sorry for the mistake.
ReplyDeleteI guess you can round...I'm not actually that strict on giving all the decimal points, but 2 is a minimum.