The inequality 10x + 20y 500 models all of the combinations of scores of 10 and 20 points that will give a total greater than 500 points in a game. What is not true about the values for x and y? A. They will whole numbers. B. They will be positive numbers. C. They will all be in the first quadrant. D. They will each be greater than 5.

Question

The inequality 10x + 20y > 500 models all of the combinations of scores of 10 and 20 points that will give a total greater than 500 points in a game. What is not true about the values for x and y? A. They will whole numbers. B. They will be positive numbers. C. They will all be in the first quadrant. D. They will each be greater than 5.

debbieg · Answer

Well, x would have to be the number of 10 point scores made in the game.

y would be the number of 20 point score made in the game.

So which, from among your choices A-D, do you think NEED NOT be true about x and y?

Or another way to look at the problem: which from among A-D MUST be true?

debbieg · Answer

A. They will whole numbers. 

------- could they be fractions? Could you have 1/2 of a score?

B. They will be positive numbers. 

-------- can you have a negative number of 10 point scores? or of 20 point scores?

C. They will all be in the first quadrant. 

--------- think about this in light of your answer about (b) above.

D. They will each be greater than 5.

--------- is it REQUIRED that x and y both be greater than 5? COULD the inequality be true if, say, x=1?

senkai · Answer

Oh!! I think I get it now... it would be D, right?