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If 2X + 3Y =1

What is X/2 + X/3 in terms of y?

By Energy1 (Energy1) on Saturday, October 09, 2004 - 11:47 am: Edit

2x = 1-3y

x/2 = (1-3y)/4
x/3 = (1-3y)/6

(6-18y+4-12y)/12
= (10-30y)/12
= (5-15y)/6

By Diruss (Diruss) on Saturday, October 09, 2004 - 12:56 pm: Edit

The actual answer is 3-5y/12

By Sonar (Sonar) on Saturday, October 09, 2004 - 08:31 pm: Edit

Eh, really? I did it out by hand and checked with an 89. Both times I got 5(1-3y)/12.

By Piman3141 (Piman3141) on Saturday, October 09, 2004 - 08:44 pm: Edit

btw, your denominator should be 24, not 12.

By Diruss (Diruss) on Sunday, October 10, 2004 - 12:54 pm: Edit

Whos denominator? ...the answer booklet says
3-5y/12

Glad im not the only one who can't do this question..

By Legendofmax (Legendofmax) on Sunday, October 10, 2004 - 02:09 pm: Edit

If 2X + 3Y =1

What is X/2 + X/3 in terms of y?

X/2 = 1/4 - 3Y/4

X/3 = 1/6 - Y/2

(1/4 - 3Y/4) + (1/6 - Y/2)

(3/12 - 3Y/4) + (2/12 - 2Y/4)

5/12 - 5Y/4

5/12 - 15Y/12

answer is (5-15Y)/12


VERIFY:
2X + 3Y =1

Let's say X is (1/4) and Y is (1/6)

X/2 is (1/8) and X/3 is (1/12), added together equal (5/24). Checking with my initial answer:

(5-15Y)/12, substituting (1/6) in for Y gives us (5-15(1/6))/12,

(5-15/6)/12

(30/6-15/6)/12
(15/6)/12
(5/2)/12
(5/24)

Therefore the answer is in fact (5-15Y)/12

By Optimizerdad (Optimizerdad) on Sunday, October 10, 2004 - 02:10 pm: Edit

I get the same answer as Sonar.

2x = 1 - 3y, so x = (1-3y)/2
x/2 + x/3 = 3x/6 + 2x/6 = 5x/6 = 5(1-3y)/12

By Legendofmax (Legendofmax) on Sunday, October 10, 2004 - 02:13 pm: Edit

I do believe your answer key is wrong Diruss

By Rmac43 (Rmac43) on Sunday, October 10, 2004 - 06:39 pm: Edit

I can't seem to start a new thread in this forum right now, so i'll just post this here.

I am having trouble with a question from the January, 2002 test in the ten real sats book. The question is number 10 in section 7. If any one would like to explain, it would be great.

Thanks a lot

By Legendofmax (Legendofmax) on Sunday, October 10, 2004 - 06:48 pm: Edit

Well a circle that passes through those points means that it has a radius equal to the distance from the center of the square to one of those points. So basically you need to find the length of half a diagonal of a square plus the half the length of another diagonal, or in order words, just find the length of a diagonal.

The 6x6 square is cut into 9 pieces, meaning each mini square is a 2x2. You want to find the diagonal, so 2^2 + 2^2 = sqrt(8).

To find the area of a circle, pi r^2, but since r is sqrt(8), r^2 is simply 8. The answer is 8pi

By Rmac43 (Rmac43) on Sunday, October 10, 2004 - 06:54 pm: Edit

thanks

By Diruss (Diruss) on Sunday, October 10, 2004 - 08:52 pm: Edit

I apologize for the innacurate information I have presented to you in the first place. The actual question was what is X/2 + y/3 in terms of why. Again....I apologize... not only do I make stupid mistakes on the Sat, I notice that I tend to do them here as well.